Article: 216599 of rec.radio.amateur.antenna From: "Jerry" References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Message-ID: Date: Wed, 24 Aug 2005 11:49:01 -0400 "Roy Lewallen" wrote in message news:11gk6v0r4tulk90@corp.supernews.com... > Frank wrote: >> . . . >> I agree with comments about adding a horizontal wire to the top of the >> vertical; it will probably be easier than a capacity hat. I am >> overloaded with work at the moment, but would like to attempt a model in >> a week or so when I have less work. > > Take a look also at a tee type arrangement. That is, a horizontal wire > with the tip of the vertical connected at or near its center. It might > have some advantages over connecting the wire's end to the vertical. But > of course it might be more involved to construct. > > Roy Lewallen, W7EL Roy, I built basically a loaded mobile antenna that went onto an airport building in Raleigh, NC (about 60 feet) I was reluctant to build it because I was afraid the people that I made it for (CAP) might not know how to do the elevated radials. I was afraid they might come back on me. I reckon I am one of those "trial and error" hams that has tried about everything in the last 40 years and I am still learning. Anyhoo, BOY was I WRONG! They put the thing on the air and it really puts out a good signal! None of us have done any measurements or NEC modeling, etc. Frankly, I was surprised as I had done very few vertical installations (well, I've got an AV8 vertical all-bander). All I know is, at the 60-70 foot level with tuned radials, it really sings! 73 Jerry K4KWH Article: 216600 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: How do I test a choke balun? Date: Wed, 24 Aug 2005 16:01:06 +0000 (UTC) Message-ID: References: <1c6d3$430a5b1a$97d55b95$23134@ALLTEL.NET> <4q0lg1dm8ro1mu692b6c2rvg3f1ojssa0s@4ax.com> <1124887862_257@spool6-east.superfeed.net> "Cecil Moore" wrote in message news:1124887862_257@spool6-east.superfeed.net... > Reg Edwards wrote: > > If the line is a whole number of 1/2-wavelengths, with a low > > resistance ground the input impedance of the coaxial outer conductor > > will also be very low and longitudinal current in the line will be at > > a maximum. Insertion of the choke will be very effective. > > To complicate things a little more, the common-mode current may > consist of standing waves. If the choke is installed at a current > minimum point, it may have little effect. > -- > 73, Cecil http://www.qsl.net/w5dxp ==================================== Dear Cec, It doesn't complicate things. It merely repeats what I have already said. When the line is an odd number of 1/4-waves long and there is an (albeit indeterminate) ground at the transmitter end, then there will be a high impedance at the choke (DUE TO STANDING WAVES) and the choke will then be wasting its time. If you havn't, moons ago, already downloaded the program then do so and read the program notes. There are so many unknowns in it the results are only approximate but nevertheless sufficiently accurate for the intended purpose - which is just to demonstrate choke behaviour. The only accurate result is the calculated-from-first-principles self-capacitance of the coil on which the impedance/frequency response depends. I had checked calculations, years back, by winding many coils of various sizes and shapes, (one 7 feet long), with various numbers of turns and measuring the coils' self-resonant frequency over the HF band using hand-held instruments with coils suspended in free space >from strings. I always knew the results would be useful at some time or other, never even dreaming about choke baluns. Did I ever tell you that for several years I was Head of a Measurements Standards Laboratory which I personally set up from scratch and which was in the 2nd echelon from the British National Physical Laboratory. The NPL. There were certain electrical parameters for which the laboratory was capable of making measurements more accurate than the NPL but for obvious political reasons it was not possible for the laboratory to claim such performance on calibration certificates. Some time after I had left the position on promotion, the wicked Mrs Thatcher had the laboratory dismantled and sold it off in bits because it did not produce any immediate, short-term profits. She was a chemist who went into politics. Often I still wonder what happened to the oven-enclosed battery of 12 standard Western cells. One day, if I can force myself to find the time, I may write my memoirs. I could tell you some amusing stories. ---- Yours, Reg, G4FGQ Article: 216601 of rec.radio.amateur.antenna From: nospam@free_.fr (Francis) Subject: Re: Dick BIRD's (G4ZU) death Date: Wed, 24 Aug 2005 16:55:48 GMT Message-ID: <430ca524.3934078@news.free.fr> References: <430aea4c$0$17200$8fcfb975@news.wanadoo.fr> <430b424f$0$27427$8fcfb975@news.wanadoo.fr> <43kmg19egdgftm0p1ll0ghda8n6411n0l6@4ax.com> Le Tue, 23 Aug 2005 12:38:15 -0400, Walter Maxwell a écrit : [...] >>> Wih all due respect to Dick Bird, isn't 'South of France' in the >>> Mediterranean? [...] (F8ND) [...] >Your message was plenty clear, JC, I was just trying to be funny. I suspect Walt to be well aware of mediterranean part of France and of the reputation of mediterranean guys, including about antenna performances they claim. ;-) I must suppose that gain antennas is eventually varying with latitude, but I don't know why, even after past 30 years of ham radio and reading of W2DU, W7EL, W8JI, DJ2LR, VE2CV, G6XN publications. Or I missed something : perhaps the answer is in EH principles, Magnetic Balun, MaxCom Matcher, Isotron or Bazooka antennas, steel wool baluns and so on ... In this case, sure I need some 40 years more of hard job around aerials. >But I do respect Dick Bird, he made great contributions to the field >of dx antennas. I do also respect Dick Bird. He made great contributions to the field of dx antennas for numerous french newcomers issued from CB world during the nineties and dreaming of the ultimate new big gun antenna with minimum obstruction, work and expense. in France, some of the last contributions of Dick were : - Les antennes "supergain" (05-06/1990) - L'antenne "ShoeBox" (02/1993) - Beam "Trigonal" à Grand Gain (04/1993) (in MEGAHERTZ Magazine.) I apologize for my english expression. Francis, F6AWN Article: 216602 of rec.radio.amateur.antenna Subject: Re: How do I test a choke balun? From: Cecil Moore Date: Wed, 24 Aug 2005 12:23:31 -0500 Message-ID: <1124904368_455@spool6-east.superfeed.net> References: <1c6d3$430a5b1a$97d55b95$23134@ALLTEL.NET> <4q0lg1dm8ro1mu692b6c2rvg3f1ojssa0s@4ax.com> <1124887862_257@spool6-east.superfeed.net> Reg Edwards wrote: > When the line is an odd number of 1/4-waves long and > there is an (albeit indeterminate) ground at the transmitter end, then > there will be a high impedance at the choke (DUE TO STANDING WAVES) > and the choke will then be wasting its time. And what I am saying is that exactly the same thing can happen NO MATTER WHAT THE LENGTH OF THE FEEDLINE if the choke is located at a current minimum point. I'm not arguing with you - just expanding upon what you said. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- Article: 216603 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <1c6d3$430a5b1a$97d55b95$23134@ALLTEL.NET> <4q0lg1dm8ro1mu692b6c2rvg3f1ojssa0s@4ax.com> <430bae83$0$32206$39cecf19@news.twtelecom.net> Subject: Re: How do I test a choke balun? Date: Wed, 24 Aug 2005 13:49:21 -0400 Message-ID: Speaking of useful data, what is the status of reflections III Sir? "Walter Maxwell" wrote in message news:vhqog19njt69qvebfp3fts92ttsplfecd9@4ax.com... > On Tue, 23 Aug 2005 18:17:23 -0500, Tom Ring > I'm pleased that you find my data useful, Tom, > > Walt Article: 216604 of rec.radio.amateur.antenna From: dplatt@radagast.org (Dave Platt) Subject: Re: what is the best filter to buy for my part 15 am.station Date: Wed, 24 Aug 2005 17:53:23 -0000 Message-ID: <11gpd0jl33sbi14@corp.supernews.com> References: <8c63b$430b8b3d$97d55b95$18531@ALLTEL.NET> <22846-430C189B-992@storefull-3277.bay.webtv.net> On Wed, 24 Aug 2005 01:50:03 -0500, dvd567@webtv.net (Pirate Radio) wrote: > >the freq will be 1700. not much power not over 5 watts also i am in the >country only a few people live around me so i can crank up the power lol >thanks for the info Scarcely seems like a "Part 15" AM station under those conditions? -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 216605 of rec.radio.amateur.antenna From: "Roger Conroy" Subject: Re: Material for Flexible Whip antenna Date: Wed, 24 Aug 2005 14:17:14 +0200 Message-ID: References: "David" wrote in message news:S3SOe.8590$FA3.4667@news-server.bigpond.net.au... >I am looking for the Black (Nylon,Polythene ???) tubing around 6mm OD > and wall thickness of 1mm for construction of 900 MHz whip antenna. > It needs to be fairly rigid as it is glued to an SMA plug. > > If anyone can advise what material is typically used and where I could > purchase > a reel of it (maybe it is even pressure tubing for pnuematics ?), it would > be much > appreciated. Australian source would be preferrable. > > Thank in advance > > Regards > > David Try a gardening shop. Drip/micro spray irrigation uses pvc tubing that might fit your requirement. Don't forget to do a microwave oven test on the material because some black plastics are carbon filled. 73 Roger ZR3RC Article: 216606 of rec.radio.amateur.antenna From: "Popocatepetle" Subject: Yaesu ATAS 25 Date: Wed, 24 Aug 2005 22:31:13 +0200 Message-ID: <430cd911$0$11067$e4fe514c@news.xs4all.nl> Does somebody had experience with the Yaesu ATAS 25.? 73's Pjotr Article: 216607 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: How do I test a choke balun? Message-ID: <945qg1hmcrnk5dpt9cues8ikgic1cu3g8r@4ax.com> References: <1c6d3$430a5b1a$97d55b95$23134@ALLTEL.NET> <4q0lg1dm8ro1mu692b6c2rvg3f1ojssa0s@4ax.com> <1124887862_257@spool6-east.superfeed.net> Date: Wed, 24 Aug 2005 20:46:39 -0400 On Wed, 24 Aug 2005 16:01:06 +0000 (UTC), "Reg Edwards" wrote: > >One day, if I can force myself to find the time, I may write my >memoirs. I could tell you some amusing stories. >---- >Yours, Reg, G4FGQ > Please force yourself, Reg, we'd all like to hear those stories. And they should be published for all to read. Walt Article: 216608 of rec.radio.amateur.antenna Date: Wed, 24 Aug 2005 19:50:28 -0500 From: Tom Ring Subject: Re: Earn 12% daily of your investment!!! References: Message-ID: <430d15d4$0$22207$39cecf19@news.twtelecom.net> Make12 wrote: > I'm going to tell you about a TOP RATED AUTOSURF program that takes 5 mins of your day and then instantly credits your account 12% of what you put in. Its that easy and everyone is going crazy about it. I have personally done this and been paid. > > This is how it works. You have to have/get your free Stormpay or E-gold account and then you put in a multiple of 6. So the minimum is $6 and maximum is $6000. Everyday you login and click the autosurf button and it will have a timer and switch pages for you. After 12 pages you will be credited INSTANTLY your 12%. Start small and keep rolling it in, or go big and make some cash. They have NOT FAILED yet to pay. After 12 days of surfing your account expires and they process the money you have made. It goes to your Stormpay or E-gold account which ever you used in 1-7 business days... THATS IT!! > > Examples > > Start Small. with just $6 dollars. 12% is .72 cents. Everyday for 12 days = 8.64 cents. Thats 2.64 PROFIT!!!. > > Go big $6000. 12% is 720.00. for 12 days.. thats 8640 = 2640 PROFIT!!!... > > Or go in between any multiple of 6. > > Thank you for looking at this all I ask is thta you use my referral link. This is not a pyramid so I don't get anything from anyone you refer. Thats how this program stays alive. They don't give you money to sign up. Its FREE to sign up, but if you don't put any money within 7 days then your account is deleted. > > Thanks here is the link. If you like it please refer your friends with YOUR referall link. Remeber I don't get anything from anybody you refer. If you don't believe me then just email their 24 hour techsupport, or their techsupport Forum where the people who pay you are the ones who answer you. Its AWESOME.. some may already be members. Just ask them. > http://www.12dailypro.com/?ref=11295 > > WOW! And this isn't a peeramyd skeem!?!? I'm there! tom Article: 216609 of rec.radio.amateur.antenna From: "Tom Donaly" Subject: Re: Earn 12% daily of your investment!!! References: <430d15d4$0$22207$39cecf19@news.twtelecom.net> Message-ID: Date: Thu, 25 Aug 2005 02:21:19 GMT Wes Stewart wrote: > On Wed, 24 Aug 2005 19:50:28 -0500, Tom Ring > wrote: > > >>Make12 wrote: >> >> >>>I'm going to tell you about a TOP RATED AUTOSURF program that takes 5 mins of your day and then instantly credits your account 12% of what you put in. Its that easy and everyone is going crazy about it. I have personally done this and been paid. >>> >>>This is how it works. You have to have/get your free Stormpay or E-gold account and then you put in a multiple of 6. So the minimum is $6 and maximum is $6000. Everyday you login and click the autosurf button and it will have a timer and switch pages for you. After 12 pages you will be credited INSTANTLY your 12%. Start small and keep rolling it in, or go big and make some cash. They have NOT FAILED yet to pay. After 12 days of surfing your account expires and they process the money you have made. It goes to your Stormpay or E-gold account which ever you used in 1-7 business days... THATS IT!! >>> >>>Examples >>> >>>Start Small. with just $6 dollars. 12% is .72 cents. Everyday for 12 days = 8.64 cents. Thats 2.64 PROFIT!!!. >>> >>>Go big $6000. 12% is 720.00. for 12 days.. thats 8640 = 2640 PROFIT!!!... >>> >>>Or go in between any multiple of 6. >>> >>>Thank you for looking at this all I ask is thta you use my referral link. This is not a pyramid so I don't get anything from anyone you refer. Thats how this program stays alive. They don't give you money to sign up. Its FREE to sign up, but if you don't put any money within 7 days then your account is deleted. >>> >>>Thanks here is the link. If you like it please refer your friends with YOUR referall link. Remeber I don't get anything from anybody you refer. If you don't believe me then just email their 24 hour techsupport, or their techsupport Forum where the people who pay you are the ones who answer you. Its AWESOME.. some may already be members. Just ask them. >>>http://www.12dailypro.com/?ref=11295 >>> >>> >> >>WOW! >> >>And this isn't a peeramyd skeem!?!? I'm there! >> >>tom > > > Damn. I have $600K sitting in one of my IRAs that I'd like to invest > for a coupla days but they will take only $6K. Plus, they don't seem > to know about the magic of compounding so I guess I'll have to pass. > > > > I expect that if you offer to give them $600,000.00, Wes, they'll take it. 73, Tom Donaly, KA6RUH Article: 216610 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: How do I test a choke balun? Message-ID: References: <1c6d3$430a5b1a$97d55b95$23134@ALLTEL.NET> <4q0lg1dm8ro1mu692b6c2rvg3f1ojssa0s@4ax.com> <430bae83$0$32206$39cecf19@news.twtelecom.net> Date: Wed, 24 Aug 2005 23:13:55 -0400 On Wed, 24 Aug 2005 13:49:21 -0400, "Fred W4JLE" wrote: >Speaking of useful data, what is the status of reflections III Sir? > >"Walter Maxwell" wrote in message >news:vhqog19njt69qvebfp3fts92ttsplfecd9@4ax.com... >> On Tue, 23 Aug 2005 18:17:23 -0500, Tom Ring >> I'm pleased that you find my data useful, Tom, >> >> Walt > Hi Fred, Reflections 3 is at the publisher. I don't know the current status, but thanks for asking. I'll keep the rraa up to date at it progresses. It'll also be announced on my web page at w2du.com. Walt Article: 216611 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Please help! Date: Wed, 24 Aug 2005 21:13:58 -0700 Message-ID: <11gqhcasdbj295d@corp.supernews.com> References: <1124791726.680838.154290@g47g2000cwa.googlegroups.com> <1124802997_993@spool6-east.superfeed.net> <1124879145.165208.200300@o13g2000cwo.googlegroups.com> andy wrote: > > If I would get some low angle radiation on 80 then would'nt mind some > performance degradation. But NEC shows that best gain would be at 90 > degrees... > Probably could get 80 another way. Ok, but I still need to find > "magical" antenna wire + feedline length combination. For that, > probably 10 to 20 metres around that fishing pole. Could I model the > vertical section as a straight (20m for example) and get same results > as if the wire was coiled. Dont want to model helixes! First, you can't just wind X meters of wire in a coil and expect it to behave in any way like X meters of wire stretched out. It doesn't work that way, because the field from each turn couples to all the other turns, and the coupling is much different than for a straight wire. Resonance will depend on the diameter of the winding, the number of turns, the turn spacing, and the length of the winding (actually, only two of the last three, since any two determine the third). If the turns are uniformly spaced, a model of a straight wire of the diameter of the coil will give you about the same pattern shape (just slightly fatter than a dipole, ho hum), but it won't tell you anything about what the impedance of the helix will be. You will get some useful information >from the straight-wire model, though. Make a note of the resistance the model shows. Then when you build your antenna, measure the resistance (which is the impedance at resonance). Divide the modeled resistance by the measured resistance and you'll have the efficiency. It might not make you happy. I'm afraid you're going to have to find resonance ~shudder~ experimentally. One additional comment. Don't worry about where NEC shows the best gain to be, unless you're using the antenna only for receiving. If using it for transmitting, pay attention only to what the gain is at the elevation angles of interest for your communication goals. Roy Lewallen, W7EL Article: 216612 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Wed, 24 Aug 2005 21:18:07 -0700 Message-ID: <11gqhk3nkjda48e@corp.supernews.com> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> hasan schiers wrote: > Now that is interesting, Roy. I was going to put up a 160 m inverted L this > summer. I am limited to only being able to go up about 45 feet, so I would > need about another 90 feet horizontal. > > Are you suggesting that it might be a better arrangement to go up the 45' > and then put up the top "T"? It might be. You might benefit from the radiation from the horizontal portion of an L, and you might not. But if it's quite low, the radiation will be mostly straight up, and a fair amount will be expended warming up the ground. Neither will occur with a T. > If so, roughly how long should the top part of > the T be (each side of center) to get me to 160? That's just what antenna modeling programs are for! Dust off your EZNEC and you'll have the answer in minutes. >. . . Roy Lewallen, W7EL Article: 216613 of rec.radio.amateur.antenna From: BKR Subject: Re: 3-phase antenna. Date: Wed, 24 Aug 2005 22:21:43 -0600 Message-ID: <11gqhq849pjtc7e@corp.supernews.com> References: <1850-430A9E91-888@storefull-3257.bay.webtv.net> <13c18$430b44b9$97d55b95$4127@ALLTEL.NET> You're darn close. A WELL rounded triangle. Fred W4JLE wrote: > The pattern would look like a triangle, so the answer to your question is > no. > > >>Reg, G4FGQ wrote: >>"There is a 3-phase transmitter feeding a 3-phase antenna via a 3-wire >>transmission line. >> >>The antenna consists of three 1/4-wave horizontal radiators spaced at >>120 degree intervals. >> >>Is the radiation pattern in the horizontal plane perfectly >>omnidirectional?" > > > Article: 216614 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Wed, 24 Aug 2005 21:44:52 -0700 Message-ID: <11gqj68743ot963@corp.supernews.com> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> Jerry wrote: > > Roy, > I built basically a loaded mobile antenna that went onto an airport > building in Raleigh, NC (about 60 feet) I was reluctant to build it because > I was afraid the people that I made it for (CAP) might not know how to do > the elevated radials. I was afraid they might come back on me. I reckon I am > one of those "trial and error" hams that has tried about everything in the > last 40 years and I am still learning. Anyhoo, BOY was I WRONG! They put > the thing on the air and it really puts out a good signal! None of us have > done any measurements or NEC modeling, etc. Frankly, I was surprised as I > had done very few vertical installations (well, I've got an AV8 vertical > all-bander). All I know is, at the 60-70 foot level with tuned radials, it > really sings! > > 73 > > Jerry > K4KWH I spend a lot of time learning about how antennas work, and try to pass the information along as best I can. But I find over and over again that most people don't have the ability to evaluate things in anything but a binary fashion -- everything has to be "good" or "bad" (or "good" and "evil"), "theory" or "experiment", "perfect" or "no good"; antennas either "work" or "don't work". So what I say is often interpreted as a statement that an antenna has to be perfect in order to work well, or to "work" at all -- whatever that means. But that's not at all what I'm saying. Let me try once again to clarify what I mean. Just about anything will radiate, from a dummy load on up. But some antennas radiate a greater fraction of the applied power than others, and some radiate more in desired directions than others. What I try to do is to understand how they work so I can, if I want, optimize an antenna for a particular purpose. (And I don't necessarily always want to -- sometimes it's not worth the trouble.) But an antenna doesn't have to be optimum in order to talk to people. It doesn't even have to be optimum to get sixty-over-nine reports and break pileups. And it doesn't even have to be anywhere near optimum in order to provide you with many pleasant QSOs. You don't have to understand anything at all about how antennas work to put one up that will give you many hours of fine QSOs -- I must have put up hundreds without having a clue about how they really worked, and I worked plenty of stations. And I, like anyone else who's been around a few years, have a handful of great stories about some really crappy antenna that worked the rare DX. (I've even done it with a crappy antenna and QRP.) What you have to understand is that you can work *more* stations, more reliably, if you do take the time and trouble (and if your yard and pocketbook will allow) to make your antenna more efficient and make it concentrate its radiation in the directions you want. But to a lot of people, it's not worth the time and trouble -- and that's fine. Some people simply aren't interested in the technical aspects of the hobby, and would rather spend their time doing something other than learning about or even modeling antennas. There's nothing at all wrong with that. Those folks won't find many of my postings to be interesting, and won't read them, which is fine. And, like I did for a long time, they'll put up plenty of antennas that work well enough -- and even from time to time one that works exceptionally well. But I hope my postings will be useful to those people who are interested in learning more about antennas and/or who enjoy squeezing more performance out of them. And I learn from this, too! Learning about antennas doesn't diminish your ability to experiment and successfully create working antennas. What it does is to give you more tools, so you can -- if you choose, but only if you choose -- make an antenna do what you want, rather than putting it up and settling for whatever it does. Roy Lewallen, W7EL Article: 216615 of rec.radio.amateur.antenna From: dvd567@webtv.net (Pirate Radio) Subject: Re: what is the best filter to buy for my part 15 am.station Date: Thu, 25 Aug 2005 01:42:54 -0500 Message-ID: <12447-430D686E-36@storefull-3272.bay.webtv.net> References: <11gpd0jl33sbi14@corp.supernews.com> well almost part 15. Article: 216616 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: A choke balun is an impedance transformer. Date: Thu, 25 Aug 2005 07:29:19 +0000 (UTC) Message-ID: An unbalanced-to-balanced tuner is an over-complicated and unwieldy-to-use collection of components. It is usually operateable over only one or two adjacent bands. The only nice thing which can be said about it is that it looks good when outside of its box. A choke balun can be inserted between a high-Zo balanced transmission line and the tuner to allow an ordinary, simple, unbalanced tuner to be used. In the range 1.8 - 30 MHz, the balun consists of a relatively few turns of twin, flexible speaker cable wound on a ferrite ring about 2 inches in diameter. Or a pair of 18-gauge plastic-insulated wires can be wound alongside each other around the core. This is mechanically more convenient, more robust and less lossy than using coaxial cable with its very small-diameter inner conductor. Furthermore, the twin-line balun, with its higher Zo impedance of roughly 120 ohms, has electrical advantages over the usually recommended 50-ohm coax. 120 ohms is intermediate in value between 450 and 600 ohms of the transmission line and the 50 ohms impedance to which it is eventually to be transformed by the tuner. This presents to the tuner a more manageable range of impedances it has to handle. The line wound on the balun has to withstand the same high voltages which arise on the main transmission line with VSWR. It is not generally appreciated that a choke balun behaves as an impedance transformer. Insofar as the tuner and transmitter are concerned it is a short length of 120-ohm line in tandem with the main balanced line which has a different impedance. The transformation ratio depends only on the length of line on the balun and on the operating frequency. It operates on the input impedance of the main line which can vary with frequency over a very wide range in a random manner. Therefore there is no fixed impedance transformation ratio between it is used. It can be considered indeterminate. In general the transformation ratio increases linearly with frequency. To keep things under control during design the length of line on the balun should not exceed about 1/10th or 1/8th of a wavelength at the highest frequency of use. The propagation velocity on the balun line is about the same as when it is drawn out straight. At 30 MHz this limits line length to about 1 metre or 3 feet or preferably less. So for the balun to be effective as a choke at 1.8 MHz the permeability of the ferrite material must be large enough to produce sufficient inductance with the number of turns on the core permitted by the restriction on line length. Here is another advantage of twin-line over coax because the propagation velocity on coax is much lower than twin line which further reduces available line length and also the possible number of turns. Even at 30 MHz, loss in the balun is very small because of the short length of line and wire thickness. A small line loss in the core material does occur because of flux which leaks outside the immediate vicinity of the line into the ferrite core. Most heating loss in the core is due to longitudinal current in the choke at the lowest operating frequency when, insofar as longitudinal current is concerned, the pair of wires behave as a single inductance-producing wire. But the power available from longitudinal currents is already lost from the antenna anyway. To mimise longitudinal current make sure there is sufficient inductance - which is the sole purpose. For the design and peformance of a choke balun download program BALCHOKE from website below. ---- ........................................................... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp ........................................................... Article: 216617 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Please help! Date: Thu, 25 Aug 2005 12:22:30 -0500 Message-ID: <1065-430DFE56-67@storefull-3257.bay.webtv.net> References: <11gqhcasdbj295d@corp.supernews.com> Roy, W7EL wrote: "First, you can`t just wind X meters of wire on a coil and expect it to behave in any way like X meters of wire stretched out." Of course, Roy is right. Yet, the more wire wound coonsistently on a form, the more inductance and the lower its self resonant frequency. My 19th edition of the "ARRL Antenna Book" offers some guidance in winding radial-mode helical antennas based on experimental results. It appears on page 6-26. It says that a 1/2-wavelength of wire wound with equal spacing between turns comes close to making a resonant 1/4-wave whip. J.L. Davis, W5LIT (now SK) in 1949 made such an antenna to use on his new Ford, with a surplus PE-103 powering his mobile rig. The antenna was wound on a bamboo fishing pole. It had such a high-Q that when he modulated,a plasma broke out at the tip of the antenna. J.L. was an operator at KXYZ and KPRC which shared a transmitting tower. He made lots of contacts using the fishing pole antenna. Best regards, Richard Harrison, KB5WZI Article: 216618 of rec.radio.amateur.antenna From: "see sea oh ecks at you aitch see dot comm" Subject: Re: what is the best filter to buy for my part 15 am.station Date: Thu, 25 Aug 2005 17:04:46 +0000 (UTC) Message-ID: References: <11gpd0jl33sbi14@corp.supernews.com> <12447-430D686E-36@storefull-3272.bay.webtv.net> Pirate Radio wrote: > well almost part 15. > Inasmuch as it's unlicensed! -- Chris Cox, N0UK/G4JEC NIC Handle: CC345 If at first you don't succeed, skydiving is not for you. Article: 216619 of rec.radio.amateur.antenna From: "Roger Conroy" Subject: Re: what is the best filter to buy for my part 15 am.station Date: Thu, 25 Aug 2005 21:26:23 +0200 Message-ID: References: <11gpd0jl33sbi14@corp.supernews.com> <12447-430D686E-36@storefull-3272.bay.webtv.net> "see sea oh ecks at you aitch see dot comm" wrote in message news:dektne$ojs$1@gabriel.uhc.com... > Pirate Radio wrote: >> well almost part 15. >> > Inasmuch as it's unlicensed! > -- > Chris Cox, N0UK/G4JEC NIC Handle: CC345 > If at first you don't succeed, skydiving is not for you. May I suggest that you direct your enquiry to the nearest FCC office. I'm sure they will be very keen to help you! Article: 216620 of rec.radio.amateur.antenna From: Slim Subject: Stupid Qestion #362 Date: Thu, 25 Aug 2005 14:25:34 -0600 Message-ID: Hi, I know nothing about electronics etc. My question is: I have an old 12' dish that is no longer in use. Is it possible to use that as a high gain FM antenna? I'm about 35 miles out of town, and located in a low point so my FM reception is poor. This 12' dish is stitting there rusting. What are the chances of removing the LNB and getting some FM reception from it? Any other uses for a 12' mesh dish? Astronomy? Radio Telescope? At present I've got it pointed right at one of the neighbours houses and it must be annoying...... :-) Cheers Article: 216621 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <1124971591.454857.181250@z14g2000cwz.googlegroups.com> Subject: Re: Antenna improvements? Date: Thu, 25 Aug 2005 16:33:57 -0400 Message-ID: Do a Google search on CFA antennas. Touted to be the most fantastic antenna since sliced bread. You might also visit fractenna.com for another source. "CD" wrote in message news:1124971591.454857.181250@z14g2000cwz.googlegroups.com... > Hey all, > > I was curious if you are aware of any new antenna developments / > techniques in regards to AM broadcasting. I'm specifically interested > in smaller AM antennas with high power ratings and a broadband response > between the AM channels. > > I've already stumbled upon DLM from the University of Rhode Island, > Fractal Antennas from UCLA, EH Antennas from Ted Hart, Isotron, etc. > > Thanks! > > CD > Article: 216622 of rec.radio.amateur.antenna From: "Herman Römer - PA9HR" Subject: TGM Hybrid Quad Antenna's Date: Thu, 25 Aug 2005 22:34:44 +0200 Message-ID: <430e2b6c$0$63072$dbd4f001@news.wanadoo.nl> Anyone around who can tell me if it is worth to buy one with a additonal reflector ? Hope someone bought the reflector as an additional kit and can tell me if it made a significant difference. Herman Römer PA9HR Article: 216623 of rec.radio.amateur.antenna From: Allodoxaphobia Subject: Re: Antenna improvements? Date: 25 Aug 2005 21:05:34 GMT Message-ID: References: <1124971591.454857.181250@z14g2000cwz.googlegroups.com> On Thu, 25 Aug 2005 12:48:54 -0000, Dave wrote: > "CD" wrote: >> >> I was curious if you are aware of any new antenna developments / >> techniques in regards to AM broadcasting. I'm specifically interested >> in smaller AM antennas with high power ratings and a broadband response >> between the AM channels. >> >> I've already stumbled upon DLM from the University of Rhode Island, >> Fractal Antennas from UCLA, EH Antennas from Ted Hart, Isotron, etc. > > you missed cfa, and plasma antennas i think. And all the antennas featured in the April issues of QST going back many decades. HI!HI! [ sloppy top-posting corrected. ] Jonesy -- Marvin L Jones | jonz | W3DHJ | linux Pueblo, Colorado | @ | Jonesy | OS/2 __ 38.24N 104.55W | config.com | DM78rf | SK Article: 216624 of rec.radio.amateur.antenna From: "Roger Conroy" Subject: Re: Stupid Qestion #362 Date: Thu, 25 Aug 2005 23:41:19 +0200 Message-ID: References: "Slim" wrote in message news:k2asg1dslqln4h4phgof62eqmj7cupvqau@4ax.com... > Hi, > I know nothing about electronics etc. My question is: > > I have an old 12' dish that is no longer in use. Is it possible to use > that as a high gain FM antenna? I'm about 35 miles out of town, and > located in a low point so my FM reception is poor. This 12' dish is > stitting there rusting. What are the chances of removing the LNB and > getting some FM reception from it? > Any other uses for a 12' mesh dish? Astronomy? Radio Telescope? > At present I've got it pointed right at one of the neighbours houses > and it must be annoying...... :-) > Cheers > It's too small to be of any use for FM broadcast band - diameter is only about 1/10 of the wavelength. Rather invest in a yagi or corner reflector for FM broadcast. 73 Roger ZR3RC Article: 216625 of rec.radio.amateur.antenna From: "Fred W4JLE" References: Subject: Re: Stupid Qestion #362 Date: Thu, 25 Aug 2005 17:48:18 -0400 Message-ID: <8cef0$430e3caa$97d55b95$18119@ALLTEL.NET> Put your ear at the feedpoint and you can listen to see if the neighbors are upset about it. "Slim" wrote in message news:k2asg1dslqln4h4phgof62eqmj7cupvqau@4ax.com... > Hi, > I know nothing about electronics etc. My question is: > > I have an old 12' dish that is no longer in use. Is it possible to use > that as a high gain FM antenna? I'm about 35 miles out of town, and > located in a low point so my FM reception is poor. This 12' dish is > stitting there rusting. What are the chances of removing the LNB and > getting some FM reception from it? > Any other uses for a 12' mesh dish? Astronomy? Radio Telescope? > At present I've got it pointed right at one of the neighbours houses > and it must be annoying...... :-) > Cheers > Article: 216626 of rec.radio.amateur.antenna From: "Hal Rosser" References: Subject: Re: Stupid Qestion #362 Message-ID: Date: Thu, 25 Aug 2005 21:05:18 -0400 If it was solid, you could use it and a microphone to pick up sounds from far away - like the ones they use on the sidelines at pro football games. but being mesh - - I'm thinking a conversion to maybe a grill. "Slim" wrote in message news:k2asg1dslqln4h4phgof62eqmj7cupvqau@4ax.com... > Hi, > I know nothing about electronics etc. My question is: > > I have an old 12' dish that is no longer in use. Is it possible to use > that as a high gain FM antenna? I'm about 35 miles out of town, and > located in a low point so my FM reception is poor. This 12' dish is > stitting there rusting. What are the chances of removing the LNB and > getting some FM reception from it? > Any other uses for a 12' mesh dish? Astronomy? Radio Telescope? > At present I've got it pointed right at one of the neighbours houses > and it must be annoying...... :-) > Cheers > Article: 216627 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Program HYPERGEO Date: Fri, 26 Aug 2005 01:20:12 +0000 (UTC) Message-ID: My apologies to people who have had no success with attempts to download program HYPERGEO from my website. I forgot to upload it. It is now waiting at the bottom of the downloading list. ---- ........................................................... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp ........................................................... Article: 216628 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Thu, 25 Aug 2005 21:15:22 -0700 Message-ID: <11gt5qqk7qqr226@corp.supernews.com> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> dansawyeror wrote: > Roy, > > Is there an EZNEC howto. I have tried to use the demo a few times and > can't seem to get started. I tried to model a simple dipole and a center > loaded vertical and got very lost. In the main window, click Help, then Contents. This is the EZNEC manual. Read the Getting Started section, and go through the "Test Drive" tutorial it directs you to. That should get you started. Roy Lewallen, W7EL Article: 216629 of rec.radio.amateur.antenna From: "News Xtra" Subject: Anyone here have personal experience with the Micro908 antenna analyst? Message-ID: <3ezPe.6027$iM2.589292@news.xtra.co.nz> Date: Fri, 26 Aug 2005 19:08:48 +1200 Comments good and bad appreciated prior to purchase. Regards, John ZL2TTM Article: 216630 of rec.radio.amateur.antenna From: "Birderman" Subject: Best Antenna for Receiving - NEWBIE Message-ID: <1125046611.272f62ab9287ee65fc91f507d9c1c2de@teranews> Date: Fri, 26 Aug 2005 09:56:55 +0100 Hi, Being a Newbie, in West London, to this hobby of SWL, I am seeking advice on best antenna to use. I have ICOM PCR1000 and Yaesu FRG100. At present I use a 25MHz-1300MHz (TANDY/RADIO SHACK) Discone for the ICOM and a long wire with HOWES ATU on the FRG. Both rigs used in first floor room so grounding is a problem as I would nead around 10m cable run to get to a ground rod, at moment connected to water pipe. The ICOM performs well with the Discone throughout its range, even on the HF. The longwire is not as long some mentioned on the websites/books, its around 8m long and slopes east/west direction, cannot install in any othe direction or increase its length. The FRG performs well but only seems to receive channels from the East and sometimes from west, channels North and South seem to be elusive. The broadcast bands work well, but HF Airband and Datamodes seem to be very weak and noisy. Since my main interest is Airband and Datamodes I would like to be able to improve my reception of these. So I hope answesrs to the following questions will help me in reolving the problems: 1/ I understand that Longwires can be directional so limit whats being received, so considering my available space would one of the vertical wide range give better alround performance with restrictions on direction. 2/ Are Dipoles directional as ? 3/ Do Dipoles need to be mounted horizontally ? 4/ Is it possible to have dipole with both elements parallel to each other or do they need the traditional arrangement of being opposite each other. 5/ Can the Dipole be made using wire with the Elements arranged in an inverted V formation ? 6/ Can Longwire be folded/bent round corners ? 7/ Is it possible to use several long wires in different directions connected to the rig simulatenously ? Any help and suggestions in resolving the above will be most appreciated. Regards Birderman West London, UK Article: 216631 of rec.radio.amateur.antenna From: "Al" Subject: OT - Oscilloscope Message-ID: Date: Fri, 26 Aug 2005 11:26:49 GMT I acquired a Tektronix 2430A digital oscilloscope and I'm having problems with it. Is there a newsgroup that would be proper to post such a question to? Thanks. Al KA5JGV San Antonio, TX Article: 216632 of rec.radio.amateur.antenna From: "Frank" References: Subject: Re: OT - Oscilloscope Message-ID: Date: Fri, 26 Aug 2005 15:32:48 GMT "Al" wrote in message news:Z%CPe.196317$0f.178522@tornado.texas.rr.com... >I acquired a Tektronix 2430A digital oscilloscope and I'm having problems >with it. Is there a newsgroup that would be proper to post such a question >to? Thanks. > > Al KA5JGV > San Antonio, TX You might try rec.radio.amateur My solution to such a problem would be to buy the service manual. Problem with oscilloscopes is you often need a scope to fix a scope. What kind of problems are you getting? Regards, Frank Article: 216633 of rec.radio.amateur.antenna From: "Frank" References: <3ezPe.6027$iM2.589292@news.xtra.co.nz> Subject: Re: Anyone here have personal experience with the Micro908 antenna analyst? Message-ID: Date: Fri, 26 Aug 2005 15:44:55 GMT > Comments good and bad appreciated prior to purchase. > Regards, > John ZL2TTM I have no experience with this particular device, but have studied the specifications available on the web. From the point of view of a low cost, single port, network analyzer it does seem to be much better than any of the others available, such as the MFJ units. As with all the units there does not seem to be any accuracy specified. I would have liked to see the ability to measure < 5 ohms, and go below 1 MHz. A Smith Chart display would also have been very useful. I think it is a good deal and would recommend it. Problem is, for the moment, they do not seem to be available. Regard, Frank Article: 216634 of rec.radio.amateur.antenna From: "Ken Bessler" Subject: Blowing up a VLF converter Message-ID: Date: Fri, 26 Aug 2005 12:03:06 -0500 I was looking for an antenna for my LF/VLF converter. The converter is from Jakson Harbor Press and uses a SA602 chip to convert 10-400 khz up to 14.010-14.400. It has 2 five pole L.P. filters (cutoff @ 500khz). For $12, it can't be beat. Anyways, I've got it running and everything that should be grounded is grounded. I've got a antenna lead with an alligator clip on it and I'm probing around, listening to WWVB. I try my 40m inverted V (fed with ladder line & coax). I get a pretty good signal on the "hot" side (the side that connects to the center of my coax) but also I get the same signal from the ground side so I left it there. The path for the 40m antenna is radio/coax/coax coil/ladderline/ antenna. The converter is hooked to the junction where the coil transitions to the ladder line. It's just a pl-259 with one side of the ladder line going into the center pin and the other side soldered to the shell. I figure I'll just go out and unhook the converter's antenna clip when I use the 40m antenna. Getting gutsy, I decided to see what would happen if I didn't unhook the converter and transmitted into the 40m antenna I tried 1/2 watt - no damage. I then tried different power levels finally ending up with a 15.2w CW carrier. No damage! I thought I'd blow my little converter. Anyone care to educate me as to why it didn't blow? Would it have blown up if I had hooked to the other side of the ladder line? Did the 2 five pole low pass filters save it? -- 73 de Ken KGØWX - Flying Pigs #-1055 Elecraft K2 #4913 Article: 216635 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: OT - Oscilloscope Date: Fri, 26 Aug 2005 11:16:48 -0700 Message-ID: <11gun4gbs4dik60@corp.supernews.com> References: Rec.radio.amateur.homebrew would a good place for that question. And if there are other groups which are better yet, the folks there could direct you to them. Roy Lewallen, W7EL Al wrote: > I acquired a Tektronix 2430A digital oscilloscope and I'm having problems > with it. Is there a newsgroup that would be proper to post such a question > to? Thanks. > > Al KA5JGV > San Antonio, TX > > Article: 216636 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Fri, 26 Aug 2005 11:18:02 -0700 Message-ID: <11gun6qpp4tr193@corp.supernews.com> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> John Ferrell wrote: > . . . > I am a perpetual antenna student! And so are we all. Roy Lewallen, W7EL Article: 216637 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Stupid Qestion #362 Date: Fri, 26 Aug 2005 11:21:10 -0700 Message-ID: <11guncm11mepcff@corp.supernews.com> References: I'll bet if you put a little microphone at the focal point, you could hear things a long way away! You could also line it with aluminum foil and use it as a solar oven. Be careful, though! The focal point will get very, VERY hot. And bright. Roy Lewallen, W7EL Article: 216638 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Blowing up a VLF converter Date: Fri, 26 Aug 2005 11:23:25 -0700 Message-ID: <11gungtfmn46a42@corp.supernews.com> References: My money's on the filter. Roy Lewallen, W7EL Ken Bessler wrote: > I was looking for an antenna for my LF/VLF converter. > The converter is from Jakson Harbor Press and uses a > SA602 chip to convert 10-400 khz up to 14.010-14.400. > It has 2 five pole L.P. filters (cutoff @ 500khz). > > For $12, it can't be beat. Anyways, I've got it running > and everything that should be grounded is grounded. I've > got a antenna lead with an alligator clip on it and I'm > probing around, listening to WWVB. I try my 40m inverted > V (fed with ladder line & coax). I get a pretty good signal > on the "hot" side (the side that connects to the center of my > coax) but also I get the same signal from the ground side so > I left it there. > > The path for the 40m antenna is radio/coax/coax coil/ladderline/ > antenna. The converter is hooked to the junction where > the coil transitions to the ladder line. It's just a pl-259 with one > side of the ladder line going into the center pin and the other side > soldered to the shell. I figure I'll just go out and unhook the > converter's antenna clip when I use the 40m antenna. > > Getting gutsy, I decided to see what would happen if I didn't > unhook the converter and transmitted into the 40m antenna > I tried 1/2 watt - no damage. I then tried different power levels > finally ending up with a 15.2w CW carrier. No damage! > > I thought I'd blow my little converter. Anyone care to educate > me as to why it didn't blow? Would it have blown up if I had > hooked to the other side of the ladder line? Did the 2 five pole > low pass filters save it? > -- > 73 de Ken KGØWX - Flying Pigs #-1055 > Elecraft K2 #4913 > > Article: 216639 of rec.radio.amateur.antenna From: dplatt@radagast.org (Dave Platt) Subject: Re: Blowing up a VLF converter Date: Fri, 26 Aug 2005 18:42:27 -0000 Message-ID: <11guokj4fm3bc3e@corp.supernews.com> References: <11gungtfmn46a42@corp.supernews.com> In article <11gungtfmn46a42@corp.supernews.com>, Roy Lewallen wrote: >> I thought I'd blow my little converter. Anyone care to educate >> me as to why it didn't blow? Would it have blown up if I had >> hooked to the other side of the ladder line? Did the 2 five pole >> low pass filters save it? >My money's on the filter. Yeah, there would be quite a lot of attenuation... five poles, and the 40-meter signal is about four octaves above the filter's nominal cutoff. I thought that the converter might possibly include a set of anti-parallel diodes between the filter and the SA604 to provide some additional strong-signal protection, but I don't see any. So, it must be that the filter attenuation was sufficient to keep the SA602 input levels below the danger threshold. I seem to recall that these little Gilbert-cell active mixers are reasonably rugged. In looking at the schematic, I do see one thing which concerns me. The filter is a pi configuration, with a .01 uF cap to ground at either end. The cap at the antenna end of the filter (C4) would tend to shunt a lot of the 40-meter signal to ground, with L1 blocking much of the rest. Seems to me that there could be two bad effects from having this circuit shunted across the antenna when the 40-meter transmitter is keyed up. For one thing, it could present a low impedance at its attachment point (depending on the length of the feedline from the upconverter to the attachment) and might adversely affect the transmitter. For another thing, if there's a significant amount of RF power getting to the front of the filter, it'll be shunted to ground through C4 (a little monolithic ceramic by the look of it) and losses in C4 might be sufficiently high to cook it and let all of its magic smoke out. If C4 does pop, the converter would still work, but there'd be one less pole of low-pass filtration. It might not be a bad idea for the OP to check C4 to see if it shows signs of overheating, and perhaps consider adding another inductor between the antenna terminal and the C4/L1 junction. This would convert the filter from a two-Pi to a three-L configuration, and increase its antenna-side impedance at HF. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 216640 of rec.radio.amateur.antenna From: "Fred W4JLE" References: Subject: Re: Blowing up a VLF converter Date: Fri, 26 Aug 2005 15:59:07 -0400 Message-ID: <5c9d3$430f748c$97d55b95$13557@ALLTEL.NET> As the filter represents a very high impedance above 500 Khz it should have protected the converter. "Ken Bessler" wrote in message news:fXHPe.5152$ct5.5069@fed1read04... > I was looking for an antenna for my LF/VLF converter. > The converter is from Jakson Harbor Press and uses a > SA602 chip to convert 10-400 khz up to 14.010-14.400. > It has 2 five pole L.P. filters (cutoff @ 500khz). > > For $12, it can't be beat. Anyways, I've got it running > and everything that should be grounded is grounded. I've > got a antenna lead with an alligator clip on it and I'm > probing around, listening to WWVB. I try my 40m inverted > V (fed with ladder line & coax). I get a pretty good signal > on the "hot" side (the side that connects to the center of my > coax) but also I get the same signal from the ground side so > I left it there. > > The path for the 40m antenna is radio/coax/coax coil/ladderline/ > antenna. The converter is hooked to the junction where > the coil transitions to the ladder line. It's just a pl-259 with one > side of the ladder line going into the center pin and the other side > soldered to the shell. I figure I'll just go out and unhook the > converter's antenna clip when I use the 40m antenna. > > Getting gutsy, I decided to see what would happen if I didn't > unhook the converter and transmitted into the 40m antenna > I tried 1/2 watt - no damage. I then tried different power levels > finally ending up with a 15.2w CW carrier. No damage! > > I thought I'd blow my little converter. Anyone care to educate > me as to why it didn't blow? Would it have blown up if I had > hooked to the other side of the ladder line? Did the 2 five pole > low pass filters save it? > -- > 73 de Ken KGØWX - Flying Pigs #-1055 > Elecraft K2 #4913 > > Article: 216641 of rec.radio.amateur.antenna From: lyonors_v@40networks.com Subject: posting 20050826 Message-ID: <430f7712.rec.radio.amateur.antenna@mail2> Date: Fri, 26 Aug 2005 13:09:54 PDT Under the Service's late-season frameworks proposal, hunting season lengths will be 60 days in both the Atlantic and Mississippi Flyways, 74 days in the Central Flyway, and 107 days in the Pacific Flyway. "Really," Roland said. "Well, that's certainly a point in your favor, my dea r. Let's have a seat, shall we?" "Why weren't you watching her?" Martin demanded. "This isn't my fault." "But now we're paying two actresses for the same part. We have to have some economies of scale going on here." Article: 216642 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: Yagi Stacking question Message-ID: References: <1125088048.029538.224550@o13g2000cwo.googlegroups.com> Date: Fri, 26 Aug 2005 17:23:23 -0400 On 26 Aug 2005 13:27:28 -0700, "DaveC" wrote: >Hi Group, >I have a Force 12 Tango 224 (4 el 2m, 2 el 6m, 2el 10m) triband yagi. I >would like to increase my gain on 2m but dont want to shell out another >almost $400 for another 224, and was considering constructing a two >meter yagi to go on top. The question is, is this doable or must >stacked yagi always be identical? >thank you! Do you mean you're considering shelling out $400 to gain 3dB? Walt, W2DU Article: 216643 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Blowing up a VLF converter Date: Fri, 26 Aug 2005 17:13:48 -0500 Message-ID: <667-430F941C-133@storefull-3255.bay.webtv.net> References: Ken Bressler, KG0WX wrote: "I was looking for an antenna for my LF/VLF converter." Over the 10-400 KHz frequency range, there are propagation variations between night and day. A tuned loop antenna of the type often used in MW broadcast radios also works in other frequency ranges including your converter input. The tuned loop is small in terms of wavelength, yet it can improve signal to noise ratio from its frequency selectivity and from its directional characteristics. It can be an air-core type or be wound on a ferrite rod. I won`t speculate why ken hasn`t destroyed his converter with his HF transmitter. Best regards, Richard Harrison, KB5WZI Article: 216644 of rec.radio.amateur.antenna From: Dino Papas Subject: Re: OT - Oscilloscope References: <11gun4gbs4dik60@corp.supernews.com> Message-ID: Date: Fri, 26 Aug 2005 19:12:40 -0400 Try "sci.electronics.equipment" -- lots of scope discussions there. GL -- Dino KL0S/4 In article <11gun4gbs4dik60@corp.supernews.com>, Roy Lewallen wrote: > Rec.radio.amateur.homebrew would a good place for that question. And if > there are other groups which are better yet, the folks there could > direct you to them. > > Roy Lewallen, W7EL > > Al wrote: > > I acquired a Tektronix 2430A digital oscilloscope and I'm having problems > > with it. Is there a newsgroup that would be proper to post such a question > > to? Thanks. > > > > Al KA5JGV > > San Antonio, TX > > > > Article: 216645 of rec.radio.amateur.antenna From: "Ken Bessler" References: <5c9d3$430f748c$97d55b95$13557@ALLTEL.NET> Subject: Re: Blowing up a VLF converter Message-ID: Date: Fri, 26 Aug 2005 18:56:55 -0500 "Fred W4JLE" wrote in message news:5c9d3$430f748c$97d55b95$13557@ALLTEL.NET... > As the filter represents a very high impedance above 500 Khz it should > have > protected the converter. > Thanks everyone for the advice - I did check for overheating and I did check to see if the addition of the converter changed either SWR or performance of my dipole. Seems OK so far. Thanks for the education! 73 de Ken KGØWX - Flying Pigs #-1055 Elecraft K2 #4913 Article: 216646 of rec.radio.amateur.antenna Date: Fri, 26 Aug 2005 19:35:03 -0500 From: Tom Ring Subject: Re: what is the best filter to buy for my part 15 am.station References: <11gpd0jl33sbi14@corp.supernews.com> <12447-430D686E-36@storefull-3272.bay.webtv.net> Message-ID: <430fb537$0$22210$39cecf19@news.twtelecom.net> Pirate Radio wrote: > well almost part 15. > Meaning not. Which is the important part. tom K0TAR Article: 216647 of rec.radio.amateur.antenna Date: Fri, 26 Aug 2005 19:45:01 -0500 From: Tom Ring Subject: Re: Yagi Stacking question References: <1125088048.029538.224550@o13g2000cwo.googlegroups.com> Message-ID: <430fb78e$0$32193$39cecf19@news.twtelecom.net> DaveC wrote: > Hi Group, > I have a Force 12 Tango 224 (4 el 2m, 2 el 6m, 2el 10m) triband yagi. I > would like to increase my gain on 2m but dont want to shell out another > almost $400 for another 224, and was considering constructing a two > meter yagi to go on top. The question is, is this doable or must > stacked yagi always be identical? > thank you! > I've been on 6,2 etc for a long time, and would never have spent that kind of money for that low gain. I would say you need to put up whatever you need for 10, a decent 12' long 4 element for 6 and whatever you can support on 2. And use 3 feedlines. You will be much better off. If you need specifics, please feel free to email me, I have decent plans for 10, 6, 222, and 432. On 2 it's best just to buy, there is so much competition that it's not worth building. tom K0TAR Article: 216648 of rec.radio.amateur.antenna From: "M.M." Subject: Re: R7000 question References: <1125107700.691479.243330@o13g2000cwo.googlegroups.com> Message-ID: Date: Fri, 26 Aug 2005 20:11:51 -0700 jabrams4@optonline.net wrote: > I disassembled my CT-3 trap (20/30 meters) and found absolutely nothing > wrong with it ... is there supposed to be a capacitor in > there, ... I believe the capacitor is the capacitance between the inner tube(s) and the outer tube. I found on mine that the connections at the ends of the coils in the traps corrode and then make a poor connection to the tubes. IIRC, they're riveted so I drilled out the rivets and replaced them with sheet metal screws. I also applied some anti oxidation paste meant for aluminum wiring...I got it at Lowe's. That seemed to help. You might check all aluminum-to-aluminum joints and and connections and clean them and apply the paste. It seems to help mine to do that periodically. You might also check inside the box. A close lightning strike a few years back wrought havoc on the matching box on mine. The R7000 is definitely not Cushcraft's best piece of work. It has been a PITA ever since I bought it several years ago from the estate of a SK who belonged to our club. The 14AVQ I bought 35 years ago was a lot better antenna, as was the Butternut I had before the 7000. You wouldn't happen to be the guy who bought the trap from K0FL, are you? I bought the box & other two traps... 73... Mark AA7TA Article: 216649 of rec.radio.amateur.antenna From: "J. Mc Laughlin" Subject: Re: Blowing up a VLF converter Date: Fri, 26 Aug 2005 23:29:57 -0400 Message-ID: <11gvnfe2otf9uda@corp.supernews.com> References: <11gungtfmn46a42@corp.supernews.com> <11guokj4fm3bc3e@corp.supernews.com> Dear Dave Platt - AE6EO You must be looking at the schematic of the converter. Where is the schematic to be found? Thanks, Mac N8TT -- J. Mc Laughlin; Michigan U.S.A. Home: JCM@Power-Net.Net "Dave Platt" wrote in message news:11guokj4fm3bc3e@corp.supernews.com... > In article <11gungtfmn46a42@corp.supernews.com>, > Roy Lewallen wrote: > > >> I thought I'd blow my little converter. Anyone care to educate > >> me as to why it didn't blow? Would it have blown up if I had > >> hooked to the other side of the ladder line? Did the 2 five pole > >> low pass filters save it? > > >My money's on the filter. > > Yeah, there would be quite a lot of attenuation... five poles, and the > 40-meter signal is about four octaves above the filter's nominal cutoff. > > I thought that the converter might possibly include a set of > anti-parallel diodes between the filter and the SA604 to provide some > additional strong-signal protection, but I don't see any. So, it must > be that the filter attenuation was sufficient to keep the SA602 input > levels below the danger threshold. I seem to recall that these little > Gilbert-cell active mixers are reasonably rugged. > > In looking at the schematic, I do see one thing which concerns me. > The filter is a pi configuration, with a .01 uF cap to ground at > either end. The cap at the antenna end of the filter (C4) would tend > to shunt a lot of the 40-meter signal to ground, with L1 blocking much > of the rest. > > Seems to me that there could be two bad effects from having this > circuit shunted across the antenna when the 40-meter transmitter is > keyed up. For one thing, it could present a low impedance at its > attachment point (depending on the length of the feedline from the > upconverter to the attachment) and might adversely affect the > transmitter. For another thing, if there's a significant amount of RF > power getting to the front of the filter, it'll be shunted to ground > through C4 (a little monolithic ceramic by the look of it) and losses > in C4 might be sufficiently high to cook it and let all of its magic > smoke out. > > If C4 does pop, the converter would still work, but there'd be one > less pole of low-pass filtration. > > It might not be a bad idea for the OP to check C4 to see if it shows > signs of overheating, and perhaps consider adding another inductor > between the antenna terminal and the C4/L1 junction. This would > convert the filter from a two-Pi to a three-L configuration, and > increase its antenna-side impedance at HF. > > -- > Dave Platt AE6EO > Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior > I do _not_ wish to receive unsolicited commercial email, and I will > boycott any company which has the gall to send me such ads! Article: 216650 of rec.radio.amateur.antenna From: "998 cc" References: Subject: Re: OT - Oscilloscope Message-ID: Date: Sat, 27 Aug 2005 04:55:15 GMT Al, There is a Tektronix scope discussion group on Yahoo. Quite a bit of action there. Good luck. Russ W6OHM "Al" wrote in message news:Z%CPe.196317$0f.178522@tornado.texas.rr.com... > I acquired a Tektronix 2430A digital oscilloscope and I'm having problems > with it. Is there a newsgroup that would be proper to post such a question > to? Thanks. > > Al KA5JGV > San Antonio, TX > > Article: 216651 of rec.radio.amateur.antenna From: dplatt@radagast.org (Dave Platt) Subject: Re: Blowing up a VLF converter Date: Sat, 27 Aug 2005 06:02:13 -0000 Message-ID: <11h00f5kvhumtd5@corp.supernews.com> References: <11gungtfmn46a42@corp.supernews.com> <11guokj4fm3bc3e@corp.supernews.com> <11gvnfe2otf9uda@corp.supernews.com> >Dear Dave Platt - AE6EO > You must be looking at the schematic of the converter. Where is the >schematic to be found? The manufacturer's page for this kit can be found at http://jacksonharbor.home.att.net/lfconv.htm You can download the manual and/or the schematic. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 216652 of rec.radio.amateur.antenna From: dvd567@webtv.net (Pirate Radio) Subject: Re: what is the best filter to buy for my part 15 am.station Date: Sat, 27 Aug 2005 01:45:00 -0500 Message-ID: <23822-43100BEC-562@storefull-3277.bay.webtv.net> References: <430fb537$0$22210$39cecf19@news.twtelecom.net> ok guys the station is on the air i set the freq on 1700. and a very long wire ant . about 20 ft high over 100ft of wire damm took most of the day to set the post in i could only put in a big loop had my other pirate pal to help me take care out there in radio land from alabama radio Article: 216653 of rec.radio.amateur.antenna From: fmmck@aol.com (Fred McKenzie) Subject: Re: OT - Oscilloscope Date: Fri, 26 Aug 2005 15:59:53 -0400 Message-ID: References: In article , "Al" wrote: > I acquired a Tektronix 2430A digital oscilloscope and I'm having problems > with it. Is there a newsgroup that would be proper to post such a question > to? Al- There are some sharp guys here that may be able to help, but as you noted it is a bit off topic. Try sci.electronics.equipment and/or sci.electronics.repair. 73, Fred, K4DII Article: 216654 of rec.radio.amateur.antenna From: "Roger Conroy" Subject: Re: Stupid Qestion #362 Date: Sat, 27 Aug 2005 15:15:05 +0200 Message-ID: References: <1125094600.974714.220260@g47g2000cwa.googlegroups.com> "K7ITM" wrote in message news:1125094600.974714.220260@g47g2000cwa.googlegroups.com... > Roger wrote: >>It's too small to be of any use for FM broadcast band - diameter is only >>about 1/10 of the wavelength. >>Rather invest in a yagi or corner reflector for FM broadcast. > > More like one wavelength: it's a bit over 3 meters. Still, as you > say, it's too small. > > Elevation of the antenna will do more good than anything else, if > you're in a bit of a low spot. Pick an FM antenna with some gain > (Yagi, for example) and get it up as high as you reasonably can. It's > a lot easier to get an FM Yagi up a few tens of feet than it is to get > a 12 foot dish up that high! > > Cheers, > Tom Oops! my mistake - I read inches instead of feet! Not really used to ye olde english measuring system. Much happier in metric. 73 Roger ZR3RC Article: 216655 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <430fb537$0$22210$39cecf19@news.twtelecom.net> <23822-43100BEC-562@storefull-3277.bay.webtv.net> Subject: Re: what is the best filter to buy for my part 15 am.station Date: Sat, 27 Aug 2005 12:18:48 -0400 Message-ID: <363b2$4310926d$97d55b95$19061@ALLTEL.NET> 100 foot of wire on 1700Khz is not a correct length antenna. It is unlikely that your "part 15" device is matched to the new antenna, and may be worse than the legal antenna that came with it. You did not mention what you were using as RF ground. "Pirate Radio" wrote in message news:23822-43100BEC-562@storefull-3277.bay.webtv.net... > ok guys the station is on the air i set the freq on 1700. and a very > long wire ant . about 20 ft high over 100ft of wire damm took most of > the day to set the post in i could only put in a big loop had my other > pirate pal to help me take care out there in radio land from alabama > radio > Article: 216656 of rec.radio.amateur.antenna From: John Smith Subject: Re: what is the best filter to buy for my part 15 am.station Message-ID: References: <430fb537$0$22210$39cecf19@news.twtelecom.net> <23822-43100BEC-562@storefull-3277.bay.webtv.net> Date: Sat, 27 Aug 2005 09:45:24 -0700 PR: Explore 1/2 wave antennas, you can load then with an inductance(s) to achieve the 1/2 wave electrical length, and they will work against a minimal counterpoise (chain fence, spare travel trailer you have parked around, metal shed, etc, etc....) Long, long ago I ran a pirate am broadcast station using an old 50 ft. tv mast with loading coils and a heavily modified gamma match which used loading coils in its construction, was able to be heard for over 100 miles in the most favorable direction running 100+ watts though an old military transmitter... back then there were many pirate stations around... John On Sat, 27 Aug 2005 01:45:00 -0500, Pirate Radio wrote: > ok guys the station is on the air i set the freq on 1700. and a very > long wire ant . about 20 ft high over 100ft of wire damm took most of > the day to set the post in i could only put in a big loop had my other > pirate pal to help me take care out there in radio land from alabama > radio Article: 216657 of rec.radio.amateur.antenna From: dvd567@webtv.net (Pirate Radio) Subject: Re: what is the best filter to buy for my part 15 am.station Date: Sat, 27 Aug 2005 13:37:36 -0500 Message-ID: <428-4310B2F0-564@storefull-3271.bay.webtv.net> References: <23822-43100BEC-562@storefull-3277.bay.webtv.net> i said over 100ft damm man chill out also i can use the ant for my shortwave also so by Article: 216658 of rec.radio.amateur.antenna From: "Penske PC27B" Subject: FS: Diamond X510MA Dual band base antenna. (used) Message-ID: Date: Sat, 27 Aug 2005 18:56:39 GMT 1-DiamondX510MA (UHF connector) The Diamond X510NA was designed for strength and performance and is pre-tuned to achieve maximum gain in both the 2m and 70cm amateur bands. (2m: 3 x 5/8 and 70cm: 8 x 5/8). It has a 3 section fiberglass radome with overlapping outer shells for added strength. It comes with stainless steel mounting hardware and radials and strong-waterproof joint couplings. X510NA Specifications Frequency: 2M/70CM (144-148 and 440-450 MHz) Gain: 8.3/11.7 dB Power: 200 watts Connector: N Height: 17.2 feet Weight: 5 Lbs. Wind Rating: 90 MPH We also carry the Diamond X510M which is the same antenna, but with an UHF (SO239) connector instead of an N connector. Universal Radio price $188.95.00 new. $115.00 for pickup or meeting in Se, Pa. only. pottsladd13@yahoo.com Article: 216659 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <23822-43100BEC-562@storefull-3277.bay.webtv.net> <428-4310B2F0-564@storefull-3271.bay.webtv.net> Subject: Re: what is the best filter to buy for my part 15 am.station Date: Sat, 27 Aug 2005 15:11:18 -0400 Message-ID: <3b000$4310bb02$97d55b95$28944@ALLTEL.NET> Hmmm! You come in asking for advise, and when given same you get defensive and profane... Next time ask your question in rec.idontwantanyonetodisagreewithwhatihavealreadydone.mymindisclosed "Pirate Radio" wrote in message news:428-4310B2F0-564@storefull-3271.bay.webtv.net... > i said over 100ft damm man chill out also i can use the ant for my > shortwave also so by > Article: 216660 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Sat, 27 Aug 2005 15:00:40 -0500 Message-ID: References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> I played with it a bit and found that converting it to a T from an L actually reduced the overall gain at 30 deg elevation and did not improve it below that. I ended up with 73' on each side of the center for the T, slightly inverted. In fact, I took the inverted L in one of my files (already constructed) and just added the 2nd wire. I, did, of course shorten the vertical section to the 42' that I have available. It did eliminate the overhead radiation, but did not significantly improve the low angle (which seems impossible), but I'll play some more. So far, it looks like the Inverted L is the better choice, even for more power at lower launch angles than the "T". (It is also easier to construct...for a quick throw it up antenna, you only need a long piece of wire and an insulator at the top, pullling as much wire as you can get to go vertical and stretching out the rest.) Then, the real work comes, putting down a good radial field before the frost. Thanks for the tip. 73 ...hasan, N0AN "Roy Lewallen" wrote in message news:11gqhk3nkjda48e@corp.supernews.com... > hasan schiers wrote: >> Now that is interesting, Roy. I was going to put up a 160 m inverted L >> this summer. I am limited to only being able to go up about 45 feet, so I >> would need about another 90 feet horizontal. >> >> Are you suggesting that it might be a better arrangement to go up the 45' >> and then put up the top "T"? > > It might be. You might benefit from the radiation from the horizontal > portion of an L, and you might not. But if it's quite low, the radiation > will be mostly straight up, and a fair amount will be expended warming up > the ground. Neither will occur with a T. > >> If so, roughly how long should the top part of the T be (each side of >> center) to get me to 160? > > That's just what antenna modeling programs are for! Dust off your EZNEC > and you'll have the answer in minutes. > > >. . . > > Roy Lewallen, W7EL Article: 216661 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Sat, 27 Aug 2005 15:26:25 -0500 Message-ID: References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> I found the error, I had to fix two conditions that I had changed in the model: Copper wire (for loss) Ground characteristics Now that both antennas have the same conditions, the T has ever so slightly better gain at 20 degrees than the Inverted L. Not enough to bother with the increased complexity, and the input Z is now down around 5 ohms for the T and 8 ohms for the L. Now, is it worth matching the 8 ohms up to 50 at the feedpoint, or just using the tuner in the shack to take care of it? (coax feed, LMR-400, about 50') ...hasan, N0AN "Roy Lewallen" wrote in message news:11gun6qpp4tr193@corp.supernews.com... > John Ferrell wrote: > > . . . >> I am a perpetual antenna student! > > And so are we all. > > Roy Lewallen, W7EL Article: 216662 of rec.radio.amateur.antenna From: "J. Mc Laughlin" Subject: Re: Blowing up a VLF converter Date: Sat, 27 Aug 2005 17:22:46 -0400 Message-ID: <11h1mash41klh92@corp.supernews.com> References: <11gungtfmn46a42@corp.supernews.com> <11guokj4fm3bc3e@corp.supernews.com> <11gvnfe2otf9uda@corp.supernews.com> <11h00f5kvhumtd5@corp.supernews.com> Dear Dave Platt - AE6EO: Thanks. I should have thought of that. Back when Navy VLF stations were still using CW, one could receive great practice by listening. I used a crystal oscillator and a simple filter to modulate the oscillator with VLF. 73, Mac N8TT -- J. Mc Laughlin; Michigan U.S.A. Home: JCM@Power-Net.Net "Dave Platt" wrote in message news:11h00f5kvhumtd5@corp.supernews.com... > >Dear Dave Platt - AE6EO > > You must be looking at the schematic of the converter. Where is the > >schematic to be found? > > The manufacturer's page for this kit can be found at > > http://jacksonharbor.home.att.net/lfconv.htm > > You can download the manual and/or the schematic. > > -- > Dave Platt AE6EO > Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior > I do _not_ wish to receive unsolicited commercial email, and I will > boycott any company which has the gall to send me such ads! Article: 216663 of rec.radio.amateur.antenna From: Jim - NN7K Subject: Re: OT - Oscilloscope References: Message-ID: Date: Sat, 27 Aug 2005 22:25:41 GMT Al, might also contact Deane Kidd (W7TYR) - he has most manuals for Tek scopes, ect, and his prices are quite reasonable. He may also help in obtaining parts for them-- try: dektyr@teleport.com Was purchaseing manager at Tek for years! as info-- Jim NN7K > "Al" wrote in message > news:Z%CPe.196317$0f.178522@tornado.texas.rr.com... > >>I acquired a Tektronix 2430A digital oscilloscope and I'm having problems >>with it. Is there a newsgroup that would be proper to post such a question >>to? Thanks. >> >>Al KA5JGV >>San Antonio, TX >> >> > > > Article: 216664 of rec.radio.amateur.antenna From: "Charlie" Subject: Re: Yagi Stacking question Date: Sat, 27 Aug 2005 17:37:54 -0500 Message-ID: <11h1qqpichh2d85@news.supernews.com> References: <1125088048.029538.224550@o13g2000cwo.googlegroups.com> <--qdnSYiEcnrQ43eRVn-og@comcast.com> Good advice on the 2M beam. I am so pleased with my M2 2M9SSB yagi at 90ft. Photos on www.ad5th.com and also on www.deepsouthnet.net -- Charlie "Tam/WB2TT" wrote in message news:--qdnSYiEcnrQ43eRVn-og@comcast.com... > > "DaveC" wrote in message > news:1125088048.029538.224550@o13g2000cwo.googlegroups.com... >> Hi Group, >> I have a Force 12 Tango 224 (4 el 2m, 2 el 6m, 2el 10m) triband yagi. I >> would like to increase my gain on 2m but dont want to shell out another >> almost $400 for another 224, and was considering constructing a two >> meter yagi to go on top. The question is, is this doable or must >> stacked yagi always be identical? >> thank you! >> > Don't do it. For $100 - 150 you can buy a 2 meter antenna that will > outperform two stacked 224s. I have a CushCraft 10 element. People sneer > at CC, but it works well. If you operate 6 meter SSB at all, I would > upgrade that next. Unless you get something big, the 4 element HyGain is > good, supposedly better than the CushCraft 5 el. If you ever get a real > tribander, avoid anything that has "Junior"as part of the name. > . > Tam/WB2TT > Article: 216665 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Sat, 27 Aug 2005 18:16:56 -0500 Message-ID: <1125184774_2081@spool6-east.superfeed.net> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> dansawyeror wrote: > Since you are talking about 50 Ohms I assume you are talking about a > transmission line. If that is the case you should definitely match the > feedline to antenna at the antenna feed point. Why is it definite? What is the loss in 50 ft. of LMR-400 at the frequency of interest when the SWR is 50/8 = 6.25:1? > Any attempt to match the > feedline with a tuner in the shack only turns the whole feedline into > part of the antenna system. Simply not true if the currents remain differentially balanced. SWR doesn't cause feedline radiation. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216666 of rec.radio.amateur.antenna Message-ID: <4310F652.8CD6B472@case_dude.com> From: case_dude Subject: Re: Earn 12% daily of your investment!!! References: Date: Sat, 27 Aug 2005 23:25:07 GMT I sent Mr. make12 an email, I'll give him DOUBLE his money if he sends it to me. Waiting for his wire transfer !! Article: 216667 of rec.radio.amateur.antenna Date: Sat, 27 Aug 2005 21:53:16 -0500 From: Tom Ring Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> Message-ID: <4311271d$0$32207$39cecf19@news.twtelecom.net> Cecil Moore wrote: > > Why is it definite? What is the loss in 50 ft. of LMR-400 at the > frequency of interest when the SWR is 50/8 = 6.25:1? > Ok, I need teaching here. Why would the loss change? The loss on the line is forced to what happens at the nominal 50 ohms doesn't it? The SWR shouldn't be able to change it unless the voltage limits are hit I would think. I need an explanation of why it wouldn't be so. Thanks. tom K0TAR Article: 216668 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Sat, 27 Aug 2005 22:29:36 -0500 Message-ID: <1125199933_2275@spool6-east.superfeed.net> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> <4310FD03.50808@comcast.net> dansawyeror wrote: > The combination of cable and antenna presents something > other then R = 50 ohms 0 reactance and the the transmission line see > discontinuities. The result is it radiates. If the currents are balanced, a 50 ohm transmission line seeing something other than a 50 ohm load does NOT cause it to radiate. If a 50 ohm unbalanced transmission line sees a 50 ohm balanced load and common-mode currents flow on the outside of the coax, it will usually result in radiation from the feedline. Simply knowing the magnitude of the feedpoint impedance doesn't tell us anything about feedline radiation. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216669 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Sat, 27 Aug 2005 22:40:25 -0500 Message-ID: <1125200582_2279@spool6-east.superfeed.net> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> <4311271d$0$32207$39cecf19@news.twtelecom.net> Tom Ring wrote: > Cecil Moore wrote: >> Why is it definite? What is the loss in 50 ft. of LMR-400 at the >> frequency of interest when the SWR is 50/8 = 6.25:1? >> > Ok, I need teaching here. Why would the loss change? The loss on the > line is forced to what happens at the nominal 50 ohms doesn't it? The > SWR shouldn't be able to change it unless the voltage limits are hit I > would think. I need an explanation of why it wouldn't be so. The loss specified on transmission line charts are usually matched-line losses (SWR=1:1). When the SWR is higher than 1:1, additional losses appear due to the higher SWR. There's a chart in my ARRL Handbook that gives those additional losses. The matched-line loss for 50 ft. of LMR-400 at 3.5 MHz is about 0.1 dB. Wes calculated the total loss at 0.4 dB but I think that must have been for 100 ft. of LMR-400 at 3.5 MHz with an SWR of 6.25:1. The higher SWR causes additional losses because the maximum current and maximum voltage is higher for the same power delivered to the load than for the matched-line case. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216670 of rec.radio.amateur.antenna From: "Frank" References: <430791C7.2040002@comcast.net> Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Message-ID: Date: Sun, 28 Aug 2005 04:50:26 GMT > The coil measures about 60 uH. The antenna is elevated about 3 feet on a > short tripod. The radials angle down the tripod legs and then out. > > The coil is about 4 inchs in diameter, number 12, wound on a fiberglass > form. It is centerloaded. I am looking at it accross the yard, it is about > 6 inches long. It is would with about a point .5 pitch. Calculations for a > 1:1 pitch predict a Q of about 450. > > Thanks, > Dan Dan, I have just run a NEC 2 model of your antenna. I have used the Sommerfeld/Norton ground, with average parameters of: Er = 13, and Sigma = 5 S/m. The top of the antenna is at 18 ft, and the base at 3 ft. I have twelve 40 ft radials, spaced at 30 deg, and within the limitations of NEC 2, placed them at 3" above ground. The first 5 ft of the radials drops from 3 ft to 3" at an angle of 45 deg. The monopole is center loaded with an inductor of Q = 450. The model has 640 (6") segments and takes 3 minutes to run (3.5 - 4.0 MHz in 50 kHz increments). What I notice is that I need 92 uH to resonate at 3.9 MHz. The input impedance is 12 ohms. I used a lumped element model for the inductor. I may try a physical helix later. These data do not seem to agree with your measured results. NEC 2, with the Sommerfeld/Norton ground solution, is supposed to give a reasonable result with wires at > 10^(-3) wavelengths above ground (Basic Antenna Modeling, Cebik p. 15-16 Nittany Scientific). Gain and take-off angle are excellent, with max gain of -3 dBi at 28 deg. elevation. The lower 3 dB point (8 deg elevation) gain is -6.6 dBi. The NEC output file indicates an antenna efficiency of 54%. A free space model shows an input impedance of 8 ohms, so your ground losses are not significant (At least with my model). Apart from adding horizontal wires, in "T" or inverted "L" fashion, I doubt any antenna you could put up would match its performance at distances over 500 miles. With 100 ft of LMR 400 the additional loss is about 0.45 dB. I would be very interested to know if anybody has any ideas why my calculations appear to be different from the measurements. Regards, Frank Article: 216671 of rec.radio.amateur.antenna From: "Ed Price" References: Subject: Re: Off topic request for info Message-ID: Date: Sat, 27 Aug 2005 23:05:09 -0700 "Larry Benko" wrote in message news:CqCdnVso65gby5TeRVn-qQ@comcast.com... > As I am getting closer to retirement I have been thinking about buying a > used spectrum analyzer since I will not have access to one at work. > Unfortunately I am not familiar with all the models from say 5 to 15 years > ago. Is there a good reference describing the different HP/Agilent, > Tektronix, etc. models and which are good and which to avoid. A quick > look on Ebay shows HP 4195A, 8561E, 8562A, 8562B, 8563E,8565A, > 8568B,8569B, 8591E, 8593E, and 8594E. Similarly for Tektronix 492P, 494P, > 495P, 495A, and 2755P. Is there some kind of a used buyers guide > available. I understand spectrum analyzers at a moderate level and > realize the differences between frequency range, external mixers, dynamic > range, bandwidth etc. but finding the specs in a manner that makes them > comparable is hard. Thanks for any advice. > > 73, Larry W0QE I have an HP-141T, with a full set of the plug-ins. Buying one of these on eBay may be risky, since so many analyzers get abused by incompetent users. I would demand a right-of-return guaranty, and better yet, a personal interface with the seller. Technically, the 141 system is great, top-of-the-line gear for 1975. But it has no automation to guide and help you, no FFT, no digital output, no way to archive data other than a Polaroid camera hood. (Actually, you can take a fairly decent digital camera picture of the display. And yes, there is an interface for an X/Y analog plotter, but who has one of those plotters anyway?) You might want to get a 141 for it's analog quality, and then do a digital interface project on your own. Don't select an HP-4195A for a spectrum analyzer. It doesn't have the full SA capabilities, although it triples as a SA, network analyzer and an impedance analyzer. You might find it much more suited to be a NA (up to 500 MHz) than anything else. It does have a 3.5" floppy, but the format is HP LIF, not DOS, so the data is not very transportable. It has an IEEE-488 I/O, so you can interface it to a PC. It's also god-awful heavy! An 8562A is sweet, because it is also a fine SA, and it will go up to 18 GHz, and then will interface with the HP-11970(?) microwave harmonic mixer series, to let you go up to 96 GHz or so. It's also a lot more portable; you can carry one for over 100 meters before your fingers get numb. I had a Tek 49x at one time; I never liked it. Subjective, true. I'd take one for free. I always considered the HP-859x series to be the cheaper descendants of the 856x series. Still, nice instruments, but maybe not yet cheap enough for retirees. The HP-8566B was HP's grand killer SA, with the 8568 being the lesser capable sister. If you could find an 8566B at a price you could pay, that would be great. The pinnacle for 1987. You can carry an 856x about two feet. Be aware that all of the instruments we have been talking about are full of proprietary modules that are no longer in the parts pipeline. The CRT's are a real problem; the only place to get another one is from a parts unit. (OK, maybe somebody has some new ones, in the box, right next to their pile of unbuilt Heathkits!) Although the HP units were all top commercial quality, something will eventually fail, and Radio Shack won't be much help. OTOH, a non-abused HP could easily outlive the average retiree. -- Ed WB6WSN El Cajon, CA USA Article: 216672 of rec.radio.amateur.antenna From: jonel@glenavon1.demon.co.uk Subject: Looking for help regarding satellie antennae Date: Sun, 28 Aug 2005 12:08:07 +0100 Message-ID: II have recently purchased a satellite receiver (ASR WS201) and I am having little success in getting it connected. I don't know if this is the correct place to seek such help, but I'm giving it a try anyway. I am located in East Anglia in the United Kingdom. According to the satellite location map I should be pointing south and low. I'm having no success in getting any signal at all and I would like to at least decide whether it is my equipment (in which case is it the antenna or the set) or is it a problem with the area I am in. I have no experience with satellite stuff and I would be grateful for any pointers about simple tests that could be carried out, or at least where I could go for help. I have tried the home page for the AMI website but there are problems with that also (www.amisb.co) Thanks John L Article: 216673 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Sun, 28 Aug 2005 07:02:03 -0500 Message-ID: References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> Thanks Wes...done...btw the antenna is for 160 meters, not 80m, so the loss is even less. It doesn't look to me like it's worth doing anything more than tuning out the mismatch in the shack. 73 ...hasan, N0AN Article: 216674 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Sun, 28 Aug 2005 07:07:50 -0500 Message-ID: References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> Dan, I appreciate your reply, but it is filled with misinformation. Consider reading some reference materials. The errors have been discussed in other responses to your post. I don't mean to insult you for trying to help, but the information you provided is so incorrect, that I couldn't let it pass. I hope no one attempts to make use of what you said...it will only compound the error. I asked simply is it worth it? (in terms of loss). Wes had the calculator software that showed the loss is insignificant, so it saves the work/complexity at the base of the antenna. Radiation from the feedline is not a function of mismatch. I'm surprised Reg didn't go apoplectic over that one. The tuner in the shack will do the job nicely. ...hasan, N0AN "dansawyeror" wrote in message news:4310DB9A.4060008@comcast.net... > Since you are talking about 50 Ohms I assume you are talking about a > transmission line. If that is the case you should definitely match the > feedline to antenna at the antenna feed point. Any attempt to match the > feedline with a tuner in the shack only turns the whole feedline into part > of the antenna system. By doing that you have lost any good work in > building the antenna. > > Dan > > hasan schiers wrote: >> I found the error, I had to fix two conditions that I had changed in the >> model: >> >> Copper wire (for loss) >> Ground characteristics >> >> Now that both antennas have the same conditions, the T has ever so >> slightly better gain at 20 degrees than the Inverted L. Not enough to >> bother with the increased complexity, and the input Z is now down around >> 5 ohms for the T and 8 ohms for the L. >> >> Now, is it worth matching the 8 ohms up to 50 at the feedpoint, or just >> using the tuner in the shack to take care of it? (coax feed, LMR-400, >> about 50') >> >> ...hasan, N0AN >> >> "Roy Lewallen" wrote in message >> news:11gun6qpp4tr193@corp.supernews.com... >> >>>John Ferrell wrote: >>> >>>>. . . >>>>I am a perpetual antenna student! >>> >>>And so are we all. >>> >>>Roy Lewallen, W7EL >> >> Article: 216675 of rec.radio.amateur.antenna From: "Bill Smith" Subject: Kenwood 870s and a Loop Message-ID: Date: Sun, 28 Aug 2005 12:57:06 GMT Hello all, My station consisted of an Icom 706MKIIG, the AH-4 tuner and a 360ft loop at 60 feet. The tuner is mounted at the loop on the roof with about 100ft of coax to the rig. I just purchased a Kenwood TS-870s with built in tuner. I'm running it on the same feedline and thru the unpowered AH-4. The built in tuner works fine and all seems good. Question: I want to remove the AH-4 to go with my 706 for mobile/remote use. Would a 1:1 balun work in place of the AH-4 to connect the loop to the feedline? I work 15 thru 80 most of the time. 73 Smitty -kb3gun Article: 216676 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Sun, 28 Aug 2005 08:27:01 -0500 Message-ID: <1125235778_967@spool6-east.superfeed.net> References: <430791C7.2040002@comcast.net> <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> <4311271d$0$32207$39cecf19@news.twtelecom.net> Tom Ring wrote: > Cecil Moore wrote: >> Why is it definite? What is the loss in 50 ft. of LMR-400 at the >> frequency of interest when the SWR is 50/8 = 6.25:1? >> > Ok, I need teaching here. Why would the loss change? The loss on the > line is forced to what happens at the nominal 50 ohms doesn't it? The > SWR shouldn't be able to change it unless the voltage limits are hit I > would think. I need an explanation of why it wouldn't be so. For the same amount of power delivered to the load, transmission line losses increase with increasing SWR. For a Z0-matched system: (PLoad = Pfor - Pref) As the load mismatch is increased, energy reflected from the mismatched load increases and is re-reflected back toward the load at the tuner Z0-match point. As the load mismatch is increased, more energy is stored in the transmission line during steady-state. This is indirect proof that reflected energy waves actually exist. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- Article: 216677 of rec.radio.amateur.antenna From: Sonny Hood Subject: Re: Jetstream 2015F coax Message-ID: References: <3pplg1913il62fpdor3ftf5sr41q45dlmj@4ax.com> Date: Sun, 28 Aug 2005 09:45:39 -0400 On Tue, 23 Aug 2005 09:13:36 GMT, Mike M. wrote: >Has anyone here tried the Jetstream 2015F coax cable from R&L? Is it >any good for a 50 ft run at 440 MHz? I have using this coax for several years. It is a flexible 9913 still with the spiral air gap. Great stuff. Beats the price of the 9913F which is foam type with the low velocity factor. K4WYS Article: 216678 of rec.radio.amateur.antenna From: "Henry Kolesnik" References: Subject: Re: OT - Oscilloscope Message-ID: Date: Sun, 28 Aug 2005 14:21:13 GMT Yahoo Groups have TekScopes@yahoogroups.com.. All you need to do is subribe and you'll get answers.. -- 73 Hank WD5JFR "Al" wrote in message news:Z%CPe.196317$0f.178522@tornado.texas.rr.com... >I acquired a Tektronix 2430A digital oscilloscope and I'm having problems >with it. Is there a newsgroup that would be proper to post such a question >to? Thanks. > > Al KA5JGV > San Antonio, TX > > > Article: 216679 of rec.radio.amateur.antenna From: "Rightrik" Subject: FS : high voltage ceramic insulators for wire antennas Date: Sun, 28 Aug 2005 17:06:22 +0200 Message-ID: <3ne27fF12j5nU1@individual.net> Hello, i have 40 nice ceramic insulators for wire antennas to sell. They are about 16 cm long, have two holes to let wire pass through (about 5 mm max wire diameter allowed). They have been made to work at HIGH voltages. Photo here : http://www.arifidenza.it/Public/data/ik5wqo/200582813302_P8280001-640x480.jpg They're on Ebay here : http://search.ebay.it/_W0QQsassZrightrik (they're in Italy, buyer pay spedition expenses) Thank you, 73 de Riccardo IK5WQO Article: 216680 of rec.radio.amateur.antenna From: "Frank" References: <430791C7.2040002@comcast.net> Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Message-ID: <7FkQe.218016$HI.111534@edtnps84> Date: Sun, 28 Aug 2005 15:22:43 GMT > Frank, > > Thank you. Is there any way you can forward the saved parameters. This is > a screwdriver antenna, I will remeasure the coil and double check. > > My modeling of the free space antenna showed about 4 Ohms but it was with > a much simpler program. It was that program I used to measure Q. > > Thanks, > Dan Hi Dan, I have run the program to determine the precise resonance. The parameters are as follows: Inductor 89.3 uH, and resonant at 3.92 MHz. I can send you a zipped NEC output text file. It is about 190 kB. Also the NEC code I used. You can plug in the appropriate data into an Excel spread sheet. If you need any specific graphical output I can it as a JPEG file. I used the default input source of 1 V peak, which accounts for the low power values in the output file. The E-field data is far field, normalized to 1 meter. The inductor is described as a lumped element, complex impedance, of 4.9 + j2200 ohms. I arrived at this value based on your Q of 450, and just played around with the imaginary value to achieve resonance within the 75 meter band. Let me know if I can send the above information to the address shown in your posting. Regards, Frank Article: 216681 of rec.radio.amateur.antenna From: "Jerry Martes" References: Subject: Re: Looking for help regarding satellie antennae Message-ID: Date: Sun, 28 Aug 2005 18:07:41 GMT wrote in message news:c963h15004nq6salpmckavrmmmulvpmfnq@4ax.com... > II have recently purchased a satellite receiver (ASR WS201) and I am > having little success in getting it connected. I don't know if this is > the correct place to seek such help, but I'm giving it a try anyway. > > I am located in East Anglia in the United Kingdom. According to the > satellite location map I should be pointing south and low. I'm having > no success in getting any signal at all and I would like to at least > decide whether it is my equipment (in which case is it the antenna or > the set) or is it a problem with the area I am in. > > I have no experience with satellite stuff and I would be grateful for > any pointers about simple tests that could be carried out, or at least > where I could go for help. I have tried the home page for the AMI > website but there are problems with that also (www.amisb.co) > > Thanks > > John L Hi John L I suppose you know that the satellite is above central Africa. That means that the antenna needs to be able to have a clear view of that point about 22,300 miles above the equator in Central Africa. The antenna with that receiver is not extreemely directional. Set the antenna in the South East angle in the Low position. Did you Google on Worldspace? Jerry Article: 216682 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Message-ID: References: <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> <4310FD03.50808@comcast.net> <6lh2h1p58928j0q4ski439ltnp67o3b3et@4ax.com> <4311E8BC.1090802@comcast.net> Date: Sun, 28 Aug 2005 14:40:24 -0400 On Sun, 28 Aug 2005 09:39:24 -0700, dansawyeror wrote: >Wes, > >As a starter, look at this site: > >http://www.cbtricks.com/~ab7if/coax/coax.htm snip > >My second claim is when the mismatch condition at the coax destination, i.e. >antenna that may result in significant radiation from the coax itself. > >Dan Well, Dan, responding to your second claim first, consider either of two situations, 1) center-fed dipole, fed with open wire line, or 2) a center fed dipole, fed with coax with an efficient choke balun. In either of these situations an impedance mismatch between the feedline and the dipole will NOT cause radiation from the feedline. And taking a look at the web site you referenced above, the writer is professing to clear some misconceptions concerning transmission line technique. However, although he does present some straight dope, he is also further spreading some misconceptions concerning SWR. As he stated, there is a lot of misunderstanding concerning the effect of line length on the amplitude of the standing wave, but he continued the incorrect information on the subject, rather than presenting a correction. The fact is, Dan, that with lossless line the SWR is NOT affected by the line length--it remains constant along the entire length of the line. And further, the ONLY affect of line length on SWR is line attenuation, which causes the SWR at the input to be less than that at the load. If you believe everything you read in that reference, you've been duped. Walt, W2DU Article: 216683 of rec.radio.amateur.antenna Subject: Super Antennas MP-1 EZNEC model Date: Sun, 28 Aug 2005 20:45:43 +0200 From: "Jochen Schaeuble" Message-ID: Hi, I think of buying a MP-1 from Super Antennas for balcony operation (I live in a small appartment with no possibility for a full blown dipole). I'm quite new to antenna modelling so I need some help for this one. Anyone can help me with this model? How do I model the coil used? Are there any already existing EZNEC files available for this antenna? Thanks in advance. vy 73 de Jochen, DG1PSI Article: 216684 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Sun, 28 Aug 2005 14:06:12 -0500 Message-ID: <1125256130_1193@spool6-east.superfeed.net> References: <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> <4310FD03.50808@comcast.net> <6lh2h1p58928j0q4ski439ltnp67o3b3et@4ax.com> <4311E89C.5070208@comcast.net> dansawyeror wrote: > My first claim is a tuner at the source does not materially improve what > is happening in the coax. That is a tuner does not recreate the > condition above where the coax is functioning as a properly matched and > terminated transmission line. All the tuner does is match the impedance > at the coax source back to some known, usually 50 Ohm, value. No matter what the voltages and currents are, if they are balanced, the transmission line won't radiate (much). If the SWR is 100:1 and the currents are balanced, the transmission won't radiate (much). If the SWR is 1:1 and the currents are unbalanced, the feedline is likely to radiate. > My second claim is when the mismatch condition at the coax destination, > i.e. antenna that may result in significant radiation from the coax itself. Please understand it is not impedance mismatches that cause radiation >from the feedline. It is unbalance in the feedline currents that causes feedline radiation. Current imbalance and impedance mismatches are not necessarily related. Current imbalance in a matched system can cause feedline radiation. Impedance mismatches can exist with negligible feedline radiation. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216685 of rec.radio.amateur.antenna From: "Penske PC27B" References: Subject: Re:(SOLD) Diamond X510MA Dual band base antenna. (used) Message-ID: Date: Sun, 28 Aug 2005 20:44:10 GMT Antenna is sold, thanks!! Article: 216686 of rec.radio.amateur.antenna From: "News Xtra" Subject: Diamond W8010 any ideas? Message-ID: Date: Mon, 29 Aug 2005 13:29:01 +1200 I'm thinking of the Diamond W8010 multiband with traps. Has anybody tried one or can anyone give an idea for the performance of a multiband dipole with traps. It is about 20 meters across the top and has 2 traps each side. It does 80-10 meters. Regards, John ZL2TTM Article: 216687 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Sun, 28 Aug 2005 22:51:41 -0500 Message-ID: <1064-4312864D-955@storefull-3257.bay.webtv.net> References: Somone wrote: "My second claim is when the mismatch condition at the coax destination, i.e. antenna that may result in significant radiation from the coax itself." Responses already show this is untrue. Radiation from the external coax surface comes from launching a signal on that surface. Good coax does not let signals penetrate its shield. A mismatch between a transmission line and its attached antenna affects both transmitting and receiving from the antenna, but does not launch signals on the outside of the coax. A mismatched transmitting antenna does not accept all available power incident upon it and reflects a portion back toward the sender depending on how bad the mismatch is. A mismatched receiving antenna has a source resistance (radiation resistance) and may also have reactance. A conjugate match is needed for maximum power transfer to the feedline. The mismatched antenna will either not extract all the power available to it in the passing wave or else reradiate more than 50%, (with full extraction, the minimum possible reradiation is with a perfectly matched antenna). Consider a short circuit across the antenna feedpoint. 100% of the energy extracted by the antenna is reradiated. Consider an open circuit at the antenna feedpoint. Little if any power is extracted from the wave sweeping the receiving antenna. The most power is received by a receiving antenna when its radiation resistance is matched to the Zo of the feedline. In this case, 50% is the best possible received carrier power in the receiver input. Nobody tells the antenna it is a receiving antenna. It is a conductor carrying a current, never mind where it came from, so it is going to radiate. When matched resistances are involved in source (radiation resistance) and load (Zo matched), the power is split 50-50 between source and load. The radiation resistance, is the source resistance for the receiver load, and it represents the reradiation from the reeiving atenna. 50% of the received power accepted by the load is the best possible performance. Mismatch means less. Either less power accepted by the antenna or more power reradiated by by the antenna. A transmatch can make the feedline appear as a matching load at the antenna junction for receiving. If matched for both transmitting and receiving, all available power will be transmitted and received. Best regards, Richard Harrison, KB5WZI Article: 216688 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Looking for help regarding satellie antennae Date: Mon, 29 Aug 2005 01:07:41 -0500 Message-ID: <666-4312A62D-947@storefull-3255.bay.webtv.net> References: John L. wrote: "I am in East Anglia in the United Kingdom." I was in Scotland a few weeks ago. I noticed many satellite dishes and was surprised at how low the elevation angles were. Most were nearly set horizontally. Some had dish feeds which were actually depressed below the horizontal. I concluded that their vertical beamwidts were deep enough to work anyway. I assumed that the users actually were getting a picture. I suspect that in Edinburg, you can start by setting the vertical angle with a carpenter`s level. It works that way with most terrestrial microwaves. In East Anglia, I suppose you are farther south and need some vertical elevation angle on your dish, but not much. You can get your bearings with a fix on the north star, some accurate maps, and information on where the bird is parked in orbit. Best regards, Richard Harrison, KB5WZI Article: 216689 of rec.radio.amateur.antenna From: Mike M. Subject: Re: Jetstream 2015F coax Message-ID: <37e5h1pfua85vcr8ce9ltp944gs47684na@4ax.com> References: <3pplg1913il62fpdor3ftf5sr41q45dlmj@4ax.com> Date: Mon, 29 Aug 2005 07:36:12 GMT On Sun, 28 Aug 2005 09:45:39 -0400, Sonny Hood wrotF: >On Tue, 23 Aug 2005 09:13:36 GMT, Mike M. >wrote: > >>Has anyone here tried the Jetstream 2015F coax cable from R&L? Is it >>any good for a 50 ft run at 440 MHz? > >I have using this coax for several years. It is a flexible 9913 still >with the spiral air gap. Great stuff. Beats the price of the 9913F >which is foam type with the low velocity factor. >K4WYS Thanks for the info. I think what you have is the 2015. What I ordered was the 2015F which has the foam insulation and the stranded center conductor. I've heard that the spiral air gap can have condensation problems. Mike Article: 216690 of rec.radio.amateur.antenna From: "Bill Smith" References: Subject: Re: Kenwood 870s and a Loop Message-ID: Date: Mon, 29 Aug 2005 11:49:35 GMT "Wes Stewart" wrote in message news:vgu4h1tgp8l8fchvq98anvpsncdq21lr2f@4ax.com... > On Sun, 28 Aug 2005 12:57:06 GMT, "Bill Smith" > wrote: > >>Hello all, >>My station consisted of an Icom 706MKIIG, the AH-4 tuner and a 360ft loop >>at >>60 feet. The tuner is mounted at the loop on the roof with about 100ft of >>coax to the rig. >> >>I just purchased a Kenwood TS-870s with built in tuner. I'm running it on >>the same feedline and thru the unpowered AH-4. The built in tuner works >>fine >>and all seems good. >> >>Question: I want to remove the AH-4 to go with my 706 for mobile/remote >>use. >>Would a 1:1 balun work in place of the AH-4 to connect the loop to the >>feedline? I work 15 thru 80 most of the time. > > > Smitty, > > I have more questions than answers. The AH4 is designed to match a > single wire (whip) antenna working against ground as best I can > figure. > > http://home.comcast.net/~hamlakemn//ah4/ah4.htm > > You say your loop is at 60' but the tuner is on the roof at the loop. > Is the roof 60' high? > > Is this a real closed loop? If so how is the tuner connected? > > With more loop parameters known, maybe it could be modeled to > determine whether a balun will function okay and whether the mismatch > on the coax will be acceptable. > > What kind of coax are you using? > > The '870 is a fine radio...got one myself. -------------------------------- Hello Wes, The loop is setup on a large, flat roof of a local business, atop 15 ft masts. Building is a 4 story brick & wood building (built in1907). No steel. One end of the loop is attached to the output (+) of the AH4, other end of the loop is attached to the ground lug of the AH4. Coax is an RG-8U (I think Belden.) from the AH4 to the radio. You are correct about the AH4 being designed to tune a wire against ground, but this loop works fine. In the past, I also rigged up a dipole to the ah4 (450ohm ladder line (+ & -) to the dipole feedpoint) and it worked well too. It's a very nice tuner (coupler). 73 Smitty -kb3gun Article: 216691 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: channel master 9512 control /rotor question Message-ID: References: <36ydnemZ4IYylY7eRVn-ug@look.ca> Date: Mon, 29 Aug 2005 13:34:18 GMT In my experience, three terminal rotators are wired wth common, ac one direction, ac the other direction. The position is timed from one end. I think the ac volts are around 14 volts. de W8CCW On Mon, 29 Aug 2005 09:06:49 -0400, "amc" wrote: >just got this from someone and i want to test it. 3 screws on each unit. >want to hook it up without frying it. >both are numbered 123, so that easy enough. but want to know whats going on >electrically, is this just a reversing switch, I'm very very novice. > >is there any free schematics out there, or can someone give me some basic >level input. I'm very green. > >Ihave a 9513 unit and I guessed at it for another antenna. > Article: 216692 of rec.radio.amateur.antenna From: W8LNA Subject: Re: channel master 9512 control /rotor question References: <36ydnemZ4IYylY7eRVn-ug@look.ca> Message-ID: Date: Mon, 29 Aug 2005 15:09:43 GMT amc wrote: > just got this from someone and i want to test it. 3 screws on each unit. > want to hook it up without frying it. > both are numbered 123, so that easy enough. but want to know whats going on > electrically, is this just a reversing switch, I'm very very novice. No, what happens is one of the terminals, say #1, is common to two (or more) windings in the motor, the other two terminals, 2 and 3, are individual connections to the other end of the individual windings. To turn the rotor AC is applied to, say, terminal 2 and through a capacitor to 3 using 1 as the return. To change direction AC is applied to 3 directly and through the capacitor to 2. The value of the capacitor and the AC voltage depends on the motor, I used a C-M motor with a Kenpro KR-400 control box and other than not having any position indication it worked just fine. I've since upgraded the motor, the box puts out about 18 VAC to drive the motor, the capacitor is about 30 uF, 60 VDC. I don't remember the terminal numbers versus coils. > > is there any free schematics out there, or can someone give me some basic > level input. I'm very green. Try http://bama.sbc.edu/ it's real slow right now, possibly because of the hurricane. There's also http://www.mods.dk/ look for 'Manuals' links in the brands' pages. My Kenpro control box manual is available under 'Other' manuals. Article: 216693 of rec.radio.amateur.antenna From: Paul Hinman Subject: sharing graves Message-ID: Date: Mon, 29 Aug 2005 15:17:01 GMT This is a multi-part message in MIME format. --------------080803070201050508080404 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit I came across an interesting antenna the other day on the web. It called for four radials for each band that one would want to use it on. In order to protect the lawn mower I would like to bury the radials. If I use insulated wires for the radials can I bury multiple radials for different frequencies in the same trench. I would rent a small trencher like they use for underground power and utility feeds, make four trenches and drop in the radials, then cover them. Thanx for any responses. Paul VE6LDS --------------080803070201050508080404 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit I came across an interesting antenna the other day on the web.  It called for four radials for each band that one would want to use it on.  In order to protect the lawn mower I would like to bury the radials.  If I use insulated wires for the radials can I bury multiple radials for different frequencies in the same trench.  I would rent a small trencher like they use for underground power and utility feeds, make four trenches and drop in the radials, then cover them.

Thanx for any responses.

Paul VE6LDS
 --------------080803070201050508080404-- Article: 216694 of rec.radio.amateur.antenna From: Mike Luther Subject: Re: sharing graves Date: Mon, 29 Aug 2005 16:09:26 +0000 Message-ID: <11h6cn5fhs3b8e9@corp.supernews.com> References: Well Paul Paul Hinman wrote: > I came across an interesting antenna the other day on the web. It > called for four radials for each band that one would want to use it > on. In order to protect the lawn mower I would like to bury the > radials. If I use insulated wires for the radials can I bury multiple > radials for different frequencies in the same trench. I would rent a > small trencher like they use for underground power and utility feeds, > make four trenches and drop in the radials, then cover them. > > Thanx for any responses. > > Paul VE6LDS > Based on practical experience with elevated 4 square vertical arrays on 40 meters, I suspect that might be a 'grave' misteak! Chortle.. I've noticed that with the elevated 4 square arrays, actual connections between elements very much change the elements in the way they present to the feed lines. I'm talking about completely grounded vertical elements and feeding each element with gamma match techniques. Note that in the common 4 square vertical low band array configuration, the spacing between the towers is roughly a quarter wave apart. That defined, it's obvious that you can proceed away from any given vertical toward another in the aray and .. you either reach or can reach it with the tip of a radial from another element. Thus you have the possibility of actually connecting the elevated radial to an opposite element's actual tower. Remember, the towers are all grounded. Your feed operation as to the gamma match section is already bonded to the vertical tower at that elevation point for the elevated radials. Not surprisingly, I've found that connection of these between tower spaces with a common wire between the towers on the elevated 4 square model DOES change the parameters required for gamma match dimensions and tuning a lot more than you might expect. Further, if you position the radials so that they extend so they don't 'aim' toward the opposite poles and toward the center, that also changes the practical match operations of the gamma match sections markedly as well. Further, even if you cross connect the between towers chort-line distance. obiously extending the radials directly opposite away from the poles, and then move toward the center where the relay switch box is located, you'll find another interesting fact about this there. Simply connecting those cross-array wires together at the relay box site also has major implications on the tuning of the gamma match sections for the towers. Recall that the 'connection' to the towers, in this case, also is the shield of the coax cable matching section which connects each element of the 4 square to the relay box at the middle of the array. If I just open up the ends of each radial from each element there where it reaches that center pole holding the relay box, I get very noticable changes on the whole array and matching differences. I can see and verify it with my MFJ antenna analyzer. I don't have the drive and desire to spend the time doing the exact match distortion paper work to define this for publication or whatever. Part of the reason to use the gamma match technique was to minimize setup time for these arrays, at the same time I solidly ground each tower for lightning protection. That last is particularly important for elevated radial vertical arrays in my very person experience at my W5WQN low band site. Based on the above, and the understanding that any given wire laying next to another wire, in any location free space or whatever, is mutually affected by the other wire, I'd think what you propose is likely to lead to a .. grave error! ;) Mike Luther - W5WQN -- --> Sleep well; OS2's still awake! ;) Mike Luther Article: 216695 of rec.radio.amateur.antenna From: "Dave" References: Subject: Re: sharing graves Message-ID: <1KGQe.74365$084.63249@attbi_s22> Date: Mon, 29 Aug 2005 16:29:49 GMT This is a multi-part message in MIME format. ------=_NextPart_000_0026_01C5AC8C.F3476AF0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable "Paul Hinman" wrote in message = news:NFFQe.330061$5V4.212744@pd7tw3no... I came across an interesting antenna the other day on the web. It = called for four radials for each band that one would want to use it on. = In order to protect the lawn mower I would like to bury the radials. If = I use insulated wires for the radials can I bury multiple radials for = different frequencies in the same trench. I would rent a small trencher = like they use for underground power and utility feeds, make four = trenches and drop in the radials, then cover them. = -------------------------------------------------------------------------= ------------------------ Why would you want to spend the money and rent a trencher? Use it for = a toy. If you have a lawn edger (if not borrow one) use that and cut a = 2 to 4 inch gruve/s in your yard and lay your radial/s in them. In about = a week they will fill in by themselves and you will never notice them. = You don't need to bury them as deep as a trencher would dig. = -------------------------------------------------------------------------= ----------------------------------------- Thanx for any responses. Paul VE6LDS ------=_NextPart_000_0026_01C5AC8C.F3476AF0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
"Paul Hinman" <paul.hinman@shaw.ca> wrote = in message=20 news:NFFQe.330061$5V4.2127= 44@pd7tw3no...
I came across an interesting antenna the other = day on the=20 web.  It called for four radials for each band that one would = want to use=20 it on.  In order to protect the lawn mower I would like to bury = the=20 radials.  If I use insulated wires for the radials can I bury = multiple=20 radials for different frequencies in the same trench.  I would = rent a=20 small trencher like they use for underground power and utility feeds, = make=20 four trenches and drop in the radials, then cover them.
----------------------------------------------------------------= ---------------------------------
Why would you want to = spend the money=20 and rent a trencher? Use it for a toy.  If you have a lawn edger = (if not=20 borrow one) use that and cut a 2 to 4 inch gruve/s in your yard and = lay your=20 radial/s in them. In about a week they will fill in by themselves = and you=20 will never notice them. You don't need to bury them as deep as a = trencher=20 would dig.
----------------------------------------------------------------= --------------------------------------------------
Thanx=20 for any responses.

Paul=20 VE6LDS
------=_NextPart_000_0026_01C5AC8C.F3476AF0-- Article: 216696 of rec.radio.amateur.antenna From: "Doug McLaren" Subject: What's in a dual band 2m/70cm antenna? Message-ID: Date: Mon, 29 Aug 2005 17:40:55 GMT I've got an HT and it's got a basic dual band 144 MHz/440 MHz antenna. It's about a meter long, which would be correct for the 144 MHz band. What makes this antenna different from a 144 MHz (only) antenna? Are there typically two conductors inside, with one 1 meter and one 35 cm? Or are the antennas typically just identical to a 144 MHz (only) antenna, and it just works at 3/4 wavelength at 70 cm? As I understand it, a 3/4 wavelength whip should work reasonably well, being resonant and having a similar impedance to a 1/4 wavelength whip. Is this correct? To be more to the point -- I've got a Kenwood D700A in my car. It has a built in duplexer, and one antenna jack. I've hooked it up to a 2 meter antenna on my roof, and it seems to work fine, both on 2m and 70cm. But I'm wondering if I'm risking ruining it ... (I haven't put a SWR meter on it yet. I probably should.) And what's so magic about 5/8 wave antennas? It's not even resonant, so obviously a matching network of some sort will be needed, but why 5/8? Why not 11/16? Or 3/4? Or something else? -- Doug McLaren, dougmc@frenzy.com, AD5RH `What's the use of happiness? It can't buy you money.' -Henny Youngman Article: 216697 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: sharing graves Date: Mon, 29 Aug 2005 17:41:01 +0000 (UTC) Message-ID: References: "Paul Hinman" wrote in message news:NFFQe.330061$5V4.212744@pd7tw3no... > I came across an interesting antenna the other day on the web. It > called for four radials for each band that one would want to use it on. > In order to protect the lawn mower I would like to bury the radials. If > I use insulated wires for the radials can I bury multiple radials for > different frequencies in the same trench. I would rent a small trencher > like they use for underground power and utility feeds, make four > trenches and drop in the radials, then cover them. > ================================= Paul, When buried, even only shallow buried, radials become almost non-resonant and their exact lengths, depth and thickness don't matter very much. What matters is the number of radials. The more radials there are the better. However there is a law of diminishing returns and after 10 or 20 have been laid, depending on soil resistivity, not much happens. But to bury a number of radials close to each other in a common trench constitutes only ONE thick radial. With 4 trenches you have only 4 radials. They behave better when wires are uniformly, radially distributed. No need to buy a digging machine. Just lay some uniformly distributed, shallow-buried wires, not necessarily all of the same length. First try about 8 wires. If after trying out the system you feel dissatisfied you can easily lay some more. ---- Reg, G4FGQ Article: 216698 of rec.radio.amateur.antenna Date: Mon, 29 Aug 2005 20:59:22 +0200 Subject: Re: Super Antennas MP-1 EZNEC model References: <1125263245.442787.236350@f14g2000cwb.googlegroups.com> From: "Jochen Schaeuble" Message-ID: Hello Gary, thanks for your comments. I guess this will get me started. vy 73 de Jochen, DG1PSI On Sun, 28 Aug 2005 23:07:25 +0200, wrote: > > Jochen Schaeuble wrote: >> Hi, >> I think of buying a MP-1 from Super Antennas for balcony operation (I >> live >> in a small appartment with no possibility for a full blown dipole). I'm >> quite new to antenna modelling so I need some help for this one. Anyone >> can help me with this model? How do I model the coil used? Are there any >> already existing EZNEC files available for this antenna? >> >> Thanks in advance. >> >> vy 73 de Jochen, DG1PSI > Jochen, The MP-1 is a short loaded vertical. The EZNEC file > "Vertical over real ground" will come close if you modify it to model > the MP-1. > The coil is modeled as a "load" placed at the proper spot on the > vertical. The inductive load should be large enough to cancel the Xc > the short vertical represents. > Eznec will tell you many parameters about the antenna. It will not > directly tell you that it will be poor on 80 and 40 meters due to > ground losses, and losses in the antenna. It should do OK on 20 meters > up. > Gary N4AST Article: 216699 of rec.radio.amateur.antenna From: "Caveat Lector" References: Subject: Re: What's in a dual band 2m/70cm antenna? Message-ID: Date: Mon, 29 Aug 2005 12:31:41 -0700 To answer one question "And what's so magic about 5/8 wave antennas? It's not even resonant, > so obviously a matching network of some sort will be needed, but why > 5/8? Why not 11/16? Or 3/4? Or something else?" So why would anyone use a 5/8 wave antenna if they have to go through all that extra work? After all, a ground plane antenna provides a nicer match. There are a couple of answers. The first is GAIN. The computer shows that the antenna (mounted 1 foot above ground) has a gain of about 1.5 dBd higher than a dipole's gain (also mounted 1 foot above ground.) The second reason you may want to use the 5/8 wave vertical is to obtain a lower angle of radiation. A half wave antenna's radiation peak angle is 20 degrees. You'll find that the 5/8 wave antenna's angle of radiation is just 16 degrees making it an even better dx antenna. See URL: http://ac3l.com/five8th.htm SOME MORE INFO About Mobile Dual-Band 2m/440 -- Roger K6XQ advises - Can I build a 2m/440mhz 5/8 mobile antenna? A 1/4 wave on 144 MHz is 3/4 wave on 440. The SWR is usually acceptable on the 3rd harmonic, although that is partly due to the increased feeder losses on 440. But SWR is not the whole story. A 3/4 wave radiator on 440 has radiation lobes that send some of your signal at high angles, not toward the horizon where you probably want it. This is usually not so severe to make the antenna unusable, and may be considered a reasonable compromise for the dual band coverage. A 5/8 wave antenna on 144 MHz is 15/8 waves on 440. If you do the simple math you will see that on 440 you will have almost a 2 wavelength antenna, which is becoming what we call a "long wire" on the HF bands. As you probably know, a long wire radiates with multiple lobes, the largest of which are toward the ends of the wire. In other words, most of your signal will be radiated up toward the sky. The reason for the coil in commercial dual band antennas is to phase the antenna currents so you actually end up with two colinear elements which both radiate at low angles, reinforcing each other and providing gain. Without the phasing coil you get multiple undesirable lobes. Also keep in mind that 5/8 wave is NOT a resonant length. There are several ways to compensate for the reactance at the base of a 5/8 wave radiator, the easiest being to add a small inductance in series which makes the antenna electrically equivalent to a 3/4 wave. (3/4 wave is resonant, as you have already discovered). Given that the gain advantage of a 5/8 wave antenna over a 1/4 wave antenna is probably not noticeable except under the most difficult conditions, and even then may or may not make a difference, my suggestion is to stick with the 1/4 wave antenna. It is simple and works OK. Above 5/8 wave the antenna exibits split lobes - so 5/8 is considered the optimum Yes it requires a matching network - but easy to implement II use a quarter wave around my area as the repeaters are usually up on mountain tops - thus a higher radiation works well. On the open highways I use a 5/8 wave -- ranges way down the road. Yep use a SWR meter and check resonance on the two bands -- now you will have piece of mind Wouldn't worry about how a dual band antenna is constructed - different schemes can be used. Just so it is resonant as speced and adjusted if it can be. -- CL -- I doubt, therefore I might be ! "Doug McLaren" wrote in message news:HMHQe.213209$gL1.115362@tornado.texas.rr.com... > I've got an HT and it's got a basic dual band 144 MHz/440 MHz antenna. > It's about a meter long, which would be correct for the 144 MHz band. > > What makes this antenna different from a 144 MHz (only) antenna? > > Are there typically two conductors inside, with one 1 meter and one 35 > cm? Or are the antennas typically just identical to a 144 MHz (only) > antenna, and it just works at 3/4 wavelength at 70 cm? > > As I understand it, a 3/4 wavelength whip should work reasonably well, > being resonant and having a similar impedance to a 1/4 wavelength > whip. Is this correct? > > To be more to the point -- I've got a Kenwood D700A in my car. It has > a built in duplexer, and one antenna jack. I've hooked it up to a 2 > meter antenna on my roof, and it seems to work fine, both on 2m and > 70cm. But I'm wondering if I'm risking ruining it ... > > (I haven't put a SWR meter on it yet. I probably should.) > > And what's so magic about 5/8 wave antennas? It's not even resonant, > so obviously a matching network of some sort will be needed, but why > 5/8? Why not 11/16? Or 3/4? Or something else? > > -- > Doug McLaren, dougmc@frenzy.com, AD5RH > `What's the use of happiness? It can't buy you money.' -Henny Youngman Article: 216700 of rec.radio.amateur.antenna Subject: Re: What's in a dual band 2m/70cm antenna? From: Cecil Moore Date: Mon, 29 Aug 2005 15:18:28 -0500 Message-ID: <1125346866_1901@spool6-east.superfeed.net> References: Doug McLaren wrote: > And what's so magic about 5/8 wave antennas? It's not even resonant, > so obviously a matching network of some sort will be needed, but why > 5/8? Why not 11/16? Or 3/4? Or something else? The free demo version of EZNEC available at www.eznec.com will answer those questions for you. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216701 of rec.radio.amateur.antenna From: "Fred W4JLE" References: Subject: Re: sharing graves Date: Mon, 29 Aug 2005 22:53:17 -0400 Message-ID: <99412$4313ca1e$97d55b95$17367@ALLTEL.NET> This is a multi-part message in MIME format. ------=_NextPart_000_0037_01C5ACEC.7219CD00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Your making it tough on yourself. Lay the wires out on the grass. Get a = bunch of coathangers that have multiplied in your closet and cut 6" = pieces and bend into a "U" shape and use them to nail the wire to the = ground. Your lawnmower will never touch them and you save the rental cost of a = trencher and clear out the coathangers. A real win win situation. "Paul Hinman" wrote in message = news:NFFQe.330061$5V4.212744@pd7tw3no... I came across an interesting antenna the other day on the web. It = called for four radials for each band that one would want to use it on. = In order to protect the lawn mower I would like to bury the radials. If = I use insulated wires for the radials can I bury multiple radials for = different frequencies in the same trench. I would rent a small trencher = like they use for underground power and utility feeds, make four = trenches and drop in the radials, then cover them. Thanx for any responses. Paul VE6LDS ------=_NextPart_000_0037_01C5ACEC.7219CD00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Your making it tough on = yourself. Lay=20 the wires out on the grass. Get a bunch of coathangers that have = multiplied in=20 your closet and cut 6" pieces and bend into a "U" shape and use them to = nail the=20 wire to the ground.
 
Your lawnmower will = never touch them=20 and you save the rental cost of a trencher and clear out the = coathangers. A real=20 win win situation.
"Paul Hinman" <paul.hinman@shaw.ca> wrote = in message=20 news:NFFQe.330061$5V4.2127= 44@pd7tw3no...
I came across an interesting antenna the other day on the = web. =20 It called for four radials for each band that one would want to use it = on.  In order to protect the lawn mower I would like to bury the=20 radials.  If I use insulated wires for the radials can I bury = multiple=20 radials for different frequencies in the same trench.  I would = rent a=20 small trencher like they use for underground power and utility feeds, = make=20 four trenches and drop in the radials, then cover them.

Thanx = for any=20 responses.

Paul VE6LDS
------=_NextPart_000_0037_01C5ACEC.7219CD00-- Article: 216702 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Tue, 30 Aug 2005 01:32:07 -0500 Message-ID: <444-4313FD67-297@storefull-3251.bay.webtv.net> References: <4313D89C.9070704@comcast.net> Dan wrote: "The whole idea of coax is to use it the way it was intended." I agree. Transmission lines don`t radiate because they are mismatched. Transmission lines radiate because they are unbalanced and this causes common-mode (unbalanced) current. In coax, the common-mode current flows on the outer surface of the shield and it radiates. Best regards, Richard Harrison, KB5WZI Article: 216703 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Tue, 30 Aug 2005 02:15:47 -0500 Message-ID: <13069-431407A3-853@storefull-3254.bay.webtv.net> References: <4313D89C.9070704@comcast.net> Dan wrote: "Simply create a model of a coax feed to a poorly tuned dipole." Dan has something there. The "ARRL Antenna Book" has an explanation of "Commonn-Mode Transmission Line Currents" on page 26-16 in my 19th edition. Launch of coax radiation is shown in Fig 24 on the same page. This picture may be worth 1000 words. Best regards, Richard Harrison, KB5WZI Article: 216704 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Tue, 30 Aug 2005 07:34:39 -0500 Message-ID: <1125405437_329@spool6-east.superfeed.net> References: <11gk6v0r4tulk90@corp.supernews.com> <430A84D1.1000005@comcast.net> <11gl9d35r5mhc97@corp.supernews.com> <11gqhk3nkjda48e@corp.supernews.com> <430E7B31.2050502@comcast.net> <11gun6qpp4tr193@corp.supernews.com> <4310DB9A.4060008@comcast.net> <1125184774_2081@spool6-east.superfeed.net> <4310FD03.50808@comcast.net> <6lh2h1p58928j0q4ski439ltnp67o3b3et@4ax.com> <4311E89C.5070208@comcast.net> <1125256130_1193@spool6-east.superfeed.net> <4313DA80.2040408@comcast.net> dansawyeror wrote: > To this point I do not know where the radiation comes from. I suspect it > is from the antenna. The easiest case is to model a poorly balanced > dipole directly feed by coax. It radiates significant power back down > the shield. Actually, a perfectly balanced dipole can also radiate from the coax shield because coax is unbalanced. Take a look at www.w2du.com and www.eznec.com for information on baluns and chokes which tend to reduce feedline radiation. It appears to me that you may be confusing "balance" with "matching". Those words have very different definitions. A balanced 50 ohm antenna fed with coax and having an SWR of 1:1 is matched but unbalanced and is likely to radiate from the feedline. A balanced 50 ohm antenna fed with 600 ohm balanced line and having an SWR of 12:1 is unmatched but balanced and is not likely to radiate much from the feedline. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216705 of rec.radio.amateur.antenna Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? From: Cecil Moore Date: Tue, 30 Aug 2005 07:38:00 -0500 Message-ID: <1125405638_335@spool6-east.superfeed.net> References: <1064-4312864D-955@storefull-3257.bay.webtv.net> <4313D89C.9070704@comcast.net> dansawyeror wrote: > Simply create a model of a coax feed to a poorly tuned dipole. Please define, "poorly tuned", "mismatched", and "unbalanced". -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216706 of rec.radio.amateur.antenna From: John Ferrell Subject: Re: sharing graves Message-ID: <0ij8h1p79cbaki1gbcb3aj391ht9rpjv2k@4ax.com> References: <99412$4313ca1e$97d55b95$17367@ALLTEL.NET> Date: Tue, 30 Aug 2005 12:38:49 GMT This has been my favorite way for a long time. The wires remain removable and pretty much become hidden in the turf after a year. A lot depends on the nature of the soil you are dealing with. North Carolina red clay in August is especially tough. Six inches is longer than I have needed. In the past I have ignored what might be optimum and instead installed the radials I could. I am inclined to use electric fence wire because it is cheap. Just use more of it. I realize that this approach is not very academic, but I feel it yields the best results in the long run for a given set of conditions. My current location seems especially prone to lightning so I expect it will be prudent to tie the radial system to the house ground with #6 copper wire. On Mon, 29 Aug 2005 22:53:17 -0400, "Fred W4JLE" wrote: >Your making it tough on yourself. Lay the wires out on the grass. Get a bunch of coathangers that have multiplied in your closet and cut 6" pieces and bend into a "U" shape and use them to nail the wire to the ground. > >Your lawnmower will never touch them and you save the rental cost of a trencher and clear out the coathangers. A real win win situation. > "Paul Hinman" wrote in message news:NFFQe.330061$5V4.212744@pd7tw3no... > I came across an interesting antenna the other day on the web. It called for four radials for each band that one would want to use it on. In order to protect the lawn mower I would like to bury the radials. If I use insulated wires for the radials can I bury multiple radials for different frequencies in the same trench. I would rent a small trencher like they use for underground power and utility feeds, make four trenches and drop in the radials, then cover them. > > Thanx for any responses. > > Paul VE6LDS Article: 216707 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Message-ID: References: <1064-4312864D-955@storefull-3257.bay.webtv.net> <4313D89C.9070704@comcast.net> Date: Tue, 30 Aug 2005 11:20:03 -0400 On Tue, 30 Aug 2005 07:13:14 -0700, Wes Stewart wrote: >On Mon, 29 Aug 2005 20:55:08 -0700, dansawyeror > wrote: > > > > >I think I've got this guy figured out; it's Fractenna come back to >haunt us. No Wes, I think it's a new guy getting his kicks from reading that new technical best seller, "Good Buddy for Dummies." Article: 216708 of rec.radio.amateur.antenna From: "Dave" Subject: Amplfier opinion Message-ID: Date: Tue, 30 Aug 2005 15:38:30 GMT I am thinking of buying the Ameritron 600 watt solid state amp and was wondering what opinions you all may have of it. Thanks Article: 216709 of rec.radio.amateur.antenna From: John Ferrell Subject: Close spaced multiband antenna Message-ID: Date: Tue, 30 Aug 2005 15:51:46 GMT Reference: Figure 7-6 of ARRL Antenna Handbook, Chapter Seven, 19 th edition For your convienience: http://www.dixienc.us/7dash6.htm Has anyone had any luck with this antenna? I have constructed a similar vertical in a "fan" shape that has performed well for me but when I start getting the wires this close together like this the results are unpredictable. I think this scheme has appeared in the Handbook for many years. de W8CCW, John Ferrell Article: 216710 of rec.radio.amateur.antenna From: Matthew Weber Subject: Re: ENOUGH OF THIS!!! Date: Tue, 30 Aug 2005 09:42:29 -0700 Message-ID: <43148C75.606@library.berkeley.edu> References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116950811.722761.163430@g47g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> Cecil Moore wrote: > Randy wrote: > >> The Christian God is not Allah, and Jesus never prayerd to Allah. > > > "Allah" is Aramaic for God. If Jesus prayed to God in Aramaic, > He prayed to Allah. Islam didn't exist when Jesus lived but > the word "Allah" certainly existed and was most likely in > Jesus' vocabulary. Not "Allah," but "El." The two names are clearly linguistically related, but they are not the same. > Yahweh, Jehovah, and Allah are all the same > Father God-head entity. What the three camps have going is nothing > but sibling rivalry Untrue. The claims of Christianity and Islam, their disciplines, and their core beliefs are different. It's simple-minded reductivism to claim that the Muslim Allah and the Christian God are the same. Muslim and Christian beliefs cannot be harmonized without doing violence to one side or the other. If one is true, then the other is false. > and I don't know whether God is laughing or > crying over those three gangs of idiots performing atrocities > in His name down through the ages. If one doesn't love Moslems, > one is not following Jesus' Christian teachings. True enough, as far as it goes. But loving Muslims doesn't imply loving everything that they do. Love isn't "being nice". Matt Article: 216711 of rec.radio.amateur.antenna From: Matthew Weber Subject: Re: ENOUGH OF THIS!!! Date: Tue, 30 Aug 2005 09:59:27 -0700 Message-ID: References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <429f10b1$0$289$cc9e4d1f@news-text.dial.pipex.com> <429f1cad$1_1@spool9-west.superfeed.net> <42a04730$1_2@spool9-west.superfeed.net> Cecil Moore wrote: > Dave Althoff, Jr. wrote: > >> Do you believe the Bible to be the "Word of God"? Or the "Words of >> God"? > > > Actually, the word or words of "Elohim", i.e. Gods. > Elohim is *PLURAL*. Yahweh was one of the Elohim. Yes, Elohim is a plural word. It doesn't necessarily signify that Yahweh is one of many gods. Some grammarians have referred to it as a "plural of majesty". -- Matthew Weber
Curatorial Assistant
Jean Gray Hargrove Music Library
University of California, Berkeley

Behold, a greater than Solomon is here.
        The Holy Bible (The New Testament):  The Gospel According to St Matthew, 12:42 Article: 216712 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Tue, 30 Aug 2005 12:14:15 -0500 Message-ID: <1066-431493E7-87@storefull-3257.bay.webtv.net> References: Wes, W7WS wrote: "--it`s Fractenna come back to haunt us." Wes is very funny. Happy Halloween! Dr. Cohen knows the difference between balance and matching, so I don`t think it`s him. Best regards, Richard Harrison, KB5WZI Article: 216713 of rec.radio.amateur.antenna From: John Smith Subject: Re: ENOUGH OF THIS!!! Message-ID: References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116950811.722761.163430@g47g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <43148C75.606@library.berkeley.edu> Date: Tue, 30 Aug 2005 10:29:43 -0700 North American Indians call him ("God") "The Great Spirit", The Great Spirit works for me, as will God, Yahweh, Jehovah, Jesus, "The Holy Spirit", "The Father", etc... Allah I would more liken to satan--"The Great Deceiver"--it which can appear to some as "An Angel of Light." It is a yin-yang thing... good-bad, light-dark, evil-good, etc... John On Tue, 30 Aug 2005 09:42:29 -0700, Matthew Weber wrote: > Cecil Moore wrote: >> Randy wrote: >> >>> The Christian God is not Allah, and Jesus never prayerd to Allah. >> >> >> "Allah" is Aramaic for God. If Jesus prayed to God in Aramaic, >> He prayed to Allah. Islam didn't exist when Jesus lived but >> the word "Allah" certainly existed and was most likely in >> Jesus' vocabulary. > > Not "Allah," but "El." The two names are clearly linguistically > related, but they are not the same. > >> Yahweh, Jehovah, and Allah are all the same >> Father God-head entity. What the three camps have going is nothing >> but sibling rivalry > > Untrue. The claims of Christianity and Islam, their disciplines, and > their core beliefs are different. It's simple-minded reductivism to > claim that the Muslim Allah and the Christian God are the same. Muslim > and Christian beliefs cannot be harmonized without doing violence to one > side or the other. If one is true, then the other is false. > >> and I don't know whether God is laughing or >> crying over those three gangs of idiots performing atrocities >> in His name down through the ages. If one doesn't love Moslems, >> one is not following Jesus' Christian teachings. > > True enough, as far as it goes. But loving Muslims doesn't imply loving > everything that they do. Love isn't "being nice". > > Matt Article: 216714 of rec.radio.amateur.antenna From: dplatt@radagast.org (Dave Platt) Subject: Re: Close spaced multiband antenna Date: Tue, 30 Aug 2005 17:46:14 -0000 Message-ID: <11h96r6bkj852d0@corp.supernews.com> References: In article , John Ferrell wrote: >Has anyone had any luck with this antenna? > >I have constructed a similar vertical in a "fan" shape that has >performed well for me but when I start getting the wires this close >together like this the results are unpredictable. I'm currently using a three-wire dipole with wire separation of about 4-5", wires cut for 40/20/10. It works quite well, with acceptable SWR across each of those bands. I'd expect the one in the ARRL handbook to have stronger coupling between the wires, due to their close proximity, and thus more interaction. Trimming it for proper operation might be trickier, and it would not surprise me if the SWR bandwidth was narrower than would be the case for a multiwire dipole with broader separation between wires. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! Article: 216715 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <1064-4312864D-955@storefull-3257.bay.webtv.net> <4313D89C.9070704@comcast.net> Subject: Re: 80 meter loaded vertical versus 80 meter loaded dipole ? Date: Tue, 30 Aug 2005 14:02:37 -0400 Message-ID: <19dae$43149f49$97d55b95$19926@ALLTEL.NET> Let opprobrious dogs lie... :>) "Wes Stewart" wrote in message news:jup8h15jdk3ckbu7ut1u8nm5hp4tojucm7@4ax.com... > I think I've got this guy figured out; it's Fractenna come back to > haunt us. Article: 216716 of rec.radio.amateur.antenna From: "MD" References: Subject: Re: Amplfier opinion Message-ID: Date: Tue, 30 Aug 2005 13:50:48 -0400 "Dave" wrote in message news:W3%Qe.291004$x96.260755@attbi_s72... > I am thinking of buying the Ameritron 600 watt solid state amp and was > wondering what opinions you all may have of it. Thanks You can read the reviews on eHam. http://www.eham.net/reviews/detail/603 Article: 216717 of rec.radio.amateur.antenna From: "Roger Conroy" Subject: Re: Looking for help regarding satellie antennae Date: Tue, 30 Aug 2005 16:43:21 +0200 Message-ID: References: <666-4312A62D-947@storefull-3255.bay.webtv.net> "Richard Harrison" wrote in message news:666-4312A62D-947@storefull-3255.bay.webtv.net... > John L. wrote: > "I am in East Anglia in the United Kingdom." > > I was in Scotland a few weeks ago. I noticed many satellite dishes and > was surprised at how low the elevation angles were. Most were nearly set > horizontally. Some had dish feeds which were actually depressed below > the horizontal. I concluded that their vertical beamwidts were deep > enough to work anyway. I assumed that the users actually were getting a > picture. I suspect that in Edinburg, you can start by setting the > vertical angle with a carpenter`s level. It works that way with most > terrestrial microwaves. In East Anglia, I suppose you are farther south > and need some vertical elevation angle on your dish, but not much. > > You can get your bearings with a fix on the north star, some accurate > maps, and information on where the bird is parked in orbit. > > Best regards, Richard Harrison, KB5WZI > Your reference to "getting a picture" implies that you are refering to satellite television. Many of the dishes have off centre feeds set below the apparent axis of the parabola. that means the incoming signal is at the oppsite angle above. Those dishes also have very narrow beamwidth making aiming VERY precise. The original poster is asking about an antenna for the Worldspace satellite radio service. The antennas used for that application have very much wider beamwidth. In addition it's a different satellite in a different location. Hope this clears the matter up a bit. 73 Roger ZR3RC Article: 216718 of rec.radio.amateur.antenna From: "John N9JG" Subject: Re: Exciter & Transmitter Date: Tue, 30 Aug 2005 15:34:45 -0500 Message-ID: References: <1125432356.646414.257460@o13g2000cwo.googlegroups.com> An exciter is a transmitter that normally drives an amplifier. "CD" wrote in message news:1125432356.646414.257460@o13g2000cwo.googlegroups.com... > Hey all, > > I've been browsing around looking at AM / FM transmitters and I keep > bumping into exciters. I'm curious. What is the difference between > exciters and transmitters? > > I'm new to broadcasting, so I'm still getting used to the lingo. > > Thanks! > Article: 216719 of rec.radio.amateur.antenna From: "Hal Rosser" References: Subject: Re: sharing graves Message-ID: Date: Tue, 30 Aug 2005 17:19:51 -0400 Like someone else said - instead of a trencher, why not try a edger. You can buy an electric edger and a long extension cord cheap enough - probably cheaper than renting a trencher. I heard one person say he just purchared a new chain for his chainsaw - and used the old chain to make the trenches for radials. Another thought - don't do radials at all - hire a front-end-loader to bury a few chain-link fence sections and tie ground to them. Be sure to grunt like the tool-man when installing the radial system - its a tradition. Article: 216720 of rec.radio.amateur.antenna From: "Hal Rosser" References: Subject: Re: Amplfier opinion Message-ID: <574Re.39$%j7.21@bignews3.bellsouth.net> Date: Tue, 30 Aug 2005 17:24:57 -0400 You don't need a linear unless you're on 80 meters - then you really need a biggie. Article: 216721 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <574Re.39$%j7.21@bignews3.bellsouth.net> Subject: Re: Amplfier opinion Date: Tue, 30 Aug 2005 17:42:58 -0400 Message-ID: Why do you need one on 80? The reality is if you can hear the other guy, he can hear you. Now if your ego requires that you have to be the first one in the pile to break through, then I guess you need a big amplifier. My pet peeve is hearing a DX station calling CQ DX and some high powered asshole starts out "Good evening again Carlos, your almost as strong as you were last night when we talked........" while some guy with a 100 watts gets to set on their thumbs until Got Rocks is through bloviating. Many are trying to get a new country while Mr. Got Rocks plays "watch this you lowly peons". Yes! you asshole in New England, I am refering to you. You splatter the entire DX window and have no regard for your fellow hams... Not one time have I heard him say, "Carlos listen for KB2***, he is trying to call you". Boy, I am glad I got that out of my system. :>) "Hal Rosser" wrote in message news:574Re.39$%j7.21@bignews3.bellsouth.net... > > You don't need a linear unless you're on 80 meters - then you really need a > biggie. > > Article: 216722 of rec.radio.amateur.antenna From: "News Xtra" Subject: Diamond W-8010 or general advise on shortened dipoles with traps or coils Message-ID: Date: Wed, 31 Aug 2005 09:59:13 +1200 The Diamond W-8010 would fit on my location. I'm not sure if it uses traps or loading coils. Does anyone have experience with this antenna or failing that, what can be expected from a shortened dipole with traps. Regards, John ZL2TTM Article: 216723 of rec.radio.amateur.antenna From: kashe@sonic.net Subject: Re: ENOUGH OF THIS!!! Message-ID: <08m9h19jb695r24v05qj6uqjmunn7mbpl3@4ax.com> References: <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <429f10b1$0$289$cc9e4d1f@news-text.dial.pipex.com> <429f1cad$1_1@spool9-west.superfeed.net> <42a04730$1_2@spool9-west.superfeed.net> Date: Tue, 30 Aug 2005 22:09:34 GMT On Tue, 30 Aug 2005 17:32:02 +0000, Scott wrote: >Where is the antenna issue(s) in this thread? I must have missed it... > DXing God? >Scott > > >Matthew Weber wrote: > >> Cecil Moore wrote: >> >>> Dave Althoff, Jr. wrote: >>> >>>> Do you believe the Bible to be the "Word of God"? Or the "Words of >>>> God"? >>> >>> >>> >>> Actually, the word or words of "Elohim", i.e. Gods. >>> Elohim is *PLURAL*. Yahweh was one of the Elohim. >> >> >> Yes, Elohim is a plural word. It doesn't necessarily signify that >> Yahweh is one of many gods. Some grammarians have referred to it as a >> "plural of majesty". >> Article: 216724 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Power radiated from feedlines Date: Tue, 30 Aug 2005 22:35:43 +0000 (UTC) Message-ID: I am truly disappointed with the long-running discourse on balanced and unbalanced feedlines and the power radiated therefrom. It's been going on for years. Nobody, especially poor novices, has ever learned anything from it. 99% of it is bafflegab. Few of us understand what on Earth is being waffled about. And those who do, prefer not to waste their time by joining in. The reason I'm making this seemingly outrageous statement is that NOBODY HAS EVER QUANTIFIED, not even once, what they are waffling about. This demonstrates a great ignorance of the subject. (Remember what Lord Kelvin said about the ability to measure and quantify what it is you are gabbing about and how that ability is directly related to what you really know about it.) Perhaps somebody might be prepared to state the power actually radiated from feedlines in watts. At least it may create the impression you know what you are talking about. It might possibly be at such a low level that, in the great majority of cases, it's not worth all the megabytes of bandwidth which are wasted on it. As an unbiased World Citizen, I now find myself half-way down a bottle of Merlo, 2000, a produce of France. But I have in reserve some decent Californian stuff. May I say how saddened I am to learn about the terrible disastrous storm which has befallen some of the Southern states. ---- Reg, G4FGQ Article: 216725 of rec.radio.amateur.antenna From: "Mr Fed UP" References: <574Re.39$%j7.21@bignews3.bellsouth.net> Subject: Re: Amplfier opinion Message-ID: Date: Tue, 30 Aug 2005 17:24:04 -0500 Yeah, is a pizzzer.. But I get a good laugh when I get through a pile up with 100 watts 10m all the way off to Mongolia. Went to sleep with a big grin knowing some of those KW big bucks bozo's missed it just because the were to busy blasting away instead of listening. Sometimes it isn't just the money and power that gets the prize. Enjoy your victories knowing it didn't cost thousands of bucks and dim your lights. Good Luck. K4TWO "Fred W4JLE" wrote in message news:e4d2c$4314d2e3$97d55b95$18080@ALLTEL.NET... > Why do you need one on 80? The reality is if you can hear the other guy, > he > can hear you. Now if your ego requires that you have to be the first one > in > the pile to break through, then I guess you need a big amplifier. > > My pet peeve is hearing a DX station calling CQ DX and some high powered > asshole starts out "Good evening again Carlos, your almost as strong as > you > were last night when we talked........" while some guy with a 100 watts > gets to set on their thumbs until Got Rocks is through bloviating. > > Many are trying to get a new country while Mr. Got Rocks plays "watch this > you lowly peons". Yes! you asshole in New England, I am refering to you. > You > splatter the entire DX window and have no regard for your fellow hams... > Not > one time have I heard him say, "Carlos listen for KB2***, he is trying to > call you". > > Boy, I am glad I got that out of my system. :>) > > "Hal Rosser" wrote in message > news:574Re.39$%j7.21@bignews3.bellsouth.net... >> >> You don't need a linear unless you're on 80 meters - then you really need > a >> biggie. >> >> > > Article: 216726 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Power radiated from feedlines Date: Tue, 30 Aug 2005 15:53:37 -0700 Message-ID: <11h9orq9cv5bh98@corp.supernews.com> References: Reg Edwards wrote: > . . . > The reason I'm making this seemingly outrageous statement is that > NOBODY HAS EVER QUANTIFIED, not even once, what they are waffling > about. This demonstrates a great ignorance of the subject. The last time you made a similar statement (not long ago) I referred you to my article on baluns, then and now available at my web site, which includes measurements of imbalance when various balun configurations are used. Have you looked at it yet? > Perhaps somebody might be prepared to state the power actually > radiated from feedlines in watts. At least it may create the > impression you know what you are talking about. > . . . Let's begin a little more simply. Can you tell us how many watts each portion of an inverted-L antenna radiates? How about each element of a Yagi? Or even, say, the outer 1/3 of a dipole? If you can't, may we assume that you don't know what you're talking about when you discuss antennas? Roy Lewallen, W7EL Article: 216727 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: sharing graves Date: Tue, 30 Aug 2005 23:36:51 +0000 (UTC) Message-ID: References: > That should have been more radials DECREASE the bandwidth. > Sorry, > ==================================== It may be considered by some that a decrease in bandwidth is a disadvantage. What really matters is that more radials result in an improvement in power radiating EFFICIENCY. Albeit with a diminishing rate of return. In ordinary garden soil, first lay about 3 or 4 shallow buried radials and test the results using the receiver S-meter. Then increase the number of radials by 50 percent and look for an improvent. If there is no measurable improvement then, to be certain, increase the number of radials by another 50 percent. Keep increasing number of radials until there is no improvement and then do a final increase of 20 or 30 percent. Even with very poor garden soil, in all probability you will not exceed 20 or 30 radials. Just ignore the ridiculous instructions in the handbooks and magazines, and from old-wives, to lay the magic number of 120 radials at the outset. Due to reciprocity, any improvement on receive, as indicated by your S-meter, will be exactly followed by the same improvement on transmit. ---- Reg, G4FGQ Article: 216728 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 00:08:30 +0000 (UTC) Message-ID: References: <11h9orq9cv5bh98@corp.supernews.com> Roy, do everybody a favour, by stating, numerically, how much power is radiated from feedlines. Then somebody might have some confidence in what you are bafflegabbing about. Are you still using your S-meter as the North American Standard? Found a corkscrew and I've just opened the Californian. I'd like to try some of your Oregon stuff - do you have any. ;o) ---- Reg. Article: 216729 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: Amplfier opinion Date: Tue, 30 Aug 2005 19:11:11 -0500 Message-ID: References: I've had mine for about 5 years and love it. I highly recommend getting an LDG AT-1000 auto antenna tuner for it. Makes a really slick combination and pretty much assures a flat load for the amp to see. (Assuming you don't need 160m as the LDG doesn't do 160). I tried some real torture tests on the LDG and it has been amazing...like feeding a 40m inverted V on 80m....terrible idea and a rotten antenna...but the LDG matched it right up. Very few auto-tuners can pass that particular test. The ALS-600 has excellent protection circuits. I have tested them on several occasions when not paying attention. The load fault circuitry works very well. I have no reservation about recommending the ALS-600. I use it on both SSB and CW, even RTTY at reduced power. I have used a TS-870s, FT-847 and TS-2000 to drive it and had no problems. IMD measurements on PSK31 indicate -30 dB with the ALS-600 running 200w output, driven by the TS-2000. Have fun. 73 ...hasan, N0AN "Dave" wrote in message news:W3%Qe.291004$x96.260755@attbi_s72... >I am thinking of buying the Ameritron 600 watt solid state amp and was > wondering what opinions you all may have of it. Thanks > > Article: 216730 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Power radiated from feedlines Date: Tue, 30 Aug 2005 17:44:00 -0700 Message-ID: <11h9vakjueh4a1e@corp.supernews.com> References: <11h9orq9cv5bh98@corp.supernews.com> Reg Edwards wrote: > Roy, do everybody a favour, by stating, numerically, how much power is > radiated from feedlines. Then somebody might have some confidence in > what you are bafflegabbing about. Of the many things I've said you disagree with, which one are you now referring to as "bafflegabbing"? And, who are "everybody" and "somebody"? You? Roy Lewallen, W7EL Reg's Old Wife & Nit-Picker and, new title, Bafflegabber Article: 216731 of rec.radio.amateur.antenna From: WCB Subject: Re: ENOUGH OF THIS!!! Date: Tue, 30 Aug 2005 20:21:39 -0500 Message-ID: <11ha0ptrqj62866@corp.supernews.com> References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <429f10b1$0$289$cc9e4d1f@news-text.dial.pipex.com> <429f1cad$1_1@spool9-west.superfeed.net> <42a04730$1_2@spool9-west.superfeed.net> Matthew Weber wrote: > Cecil Moore wrote: > >> Dave Althoff, Jr. wrote: >> >>> Do you believe the Bible to be the "Word of God"? Or the "Words of >>> God"? >> >> >> Actually, the word or words of "Elohim", i.e. Gods. >> Elohim is *PLURAL*. Yahweh was one of the Elohim. > > Yes, Elohim is a plural word. It doesn't necessarily signify that > Yahweh is one of many gods. Some grammarians have referred to it as a > "plural of majesty". > See Genesis 6, god has a number of sons, when the bible says gods, plural, it means that literally. -- Xenu is around and about, mention Hubbard, Xenu pops out! No way for the clams to stamp Xenu out, Xenu is around and about! Cheerful Charlie Article: 216732 of rec.radio.amateur.antenna From: "hasan schiers" Subject: Re: ENOUGH OF THIS!!! Date: Tue, 30 Aug 2005 20:43:55 -0500 Message-ID: References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116950811.722761.163430@g47g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <43148C75.606@library.berkeley.edu> <14i9h1hpl7d7g6bdol816cl9ck2nigktod@4ax.com> Nice work, and a jewel of objectivity and accuracy, Jon! Don't confuse the religious particularists with facts, though, it makes them grumpy. (so-called Christian, Muslim or Jewish ...they deserve each other and appear embarassingly unworthy of their Prophets, peace be upon all of them) Apologies to the list, I'll restrain myself now. I could only stand so much ignorance and propaganda. ...hasan, N0AN "J. Teske" wrote in message news:14i9h1hpl7d7g6bdol816cl9ck2nigktod@4ax.com... > On Tue, 30 Aug 2005 09:42:29 -0700, Matthew Weber > wrote: > >>Cecil Moore wrote: >>> Randy wrote: >>> >>>> The Christian God is not Allah, and Jesus never prayerd to Allah. > > In Arabic, (and I was a professional government Arabic linguist and > Middle East specialist) "Allah" means "THE God". The "AL" in Allah is > the definite article in Arabic and in the Arabic script, the definite > article gets physically linked to the word it defines. The word "god" > (lower case) ( in Arabic is Lam, Lam, Tah Marbutah or LLH. > Unfortunately I can't do Arabic script on my home computer. Also > Arabic script does not have capital letters.) That word is > transliterated LLH. (That "H" is really a glottal stop like the second > "h" in "huh." There are several Arabic letters which can be > transliterated "H" in Roman script. The Tah Marbutah, it looks like an > "o" with two dots above it, has no real equivalent in Roman script, > but is pronounced as a glottal stop. Like Hebrew, most vowels are not > written out in Arabic except in linguistic texts and the Koran...they > are simply diacrital marks. "LLH", without the definite article, was > used to described dieties in Arabic long before Muhammad and the Koran > came around in ca. 632 AD when the pre-Islamic Arabs were mainly > animists. > > From an Islamic perspective, "Allah" is the same God as the God of > Jews and the Christians. The Koran makes that quite clear. (The Koran > also argues that the Jews didn't go far enough in their beliefs and > the Christians got it wrong, but further argues that an Islamic > believer is unlikely to convert them and they should be left alone and > respected as "People of the Book.", the book in this case being the > Pentateuch.) Whether you wish to accept that concept, of course, is a > theological question. Most academic comparative theologists, even > those at Christian and Jewish seminaries who are among the believing, > do accept that premise (that the God is the same entity) even if they > don't believe in the premise that God made the Koran his last word on > the subject. The Islamic formula, as written in Arabic, states that > there is no god (indefinite article) (llh) but THE God (Allah) with > the definite article. The word has its roots in the proto-Semitic > common to Arabic, Aramaic, and Hebrew. Again, from an Islamic > perspective, Abraham, Jesus and Mohammad prayed to the same God, but > certainly the vocabulary was different. > > Your theologic milage may vary, but here is at least is a linguistic > and historical basis generally accepted in academic circles. > > > > Jon W3JT (Retired Gov't Linguist with Masters in Middle East Area > Studies.) > > Article: 216733 of rec.radio.amateur.antenna From: "Crazy George" References: <1125443164.355999.136830@g47g2000cwa.googlegroups.com> Subject: Re: Lightning Question Date: Tue, 30 Aug 2005 20:55:37 -0500 Message-ID: <43151589_3@news1.prserv.net> There is one additional step which seems, from many anecdotal references, to provide further help. Somewhere along the cable route, run the coax through at least two sections of steel electrical conduit. Size immaterial, and grounding optional. And they need not be connected together. Theories about why this works run from it forms a lossy coax for the lightning induced wave on the outside, to impedance mismatch on the outside to eddy current losses in the steel. Whatever the mechanism, I know of several locations where it seems to have reduced the damage from continuing lightning strikes. And it is certainly cheap enough to include. -- Crazy George The attglobal.net address is a SPAM trap. Please change that part to: attbiz properly formatted. wrote in message news:1125443164.355999.136830@g47g2000cwa.googlegroups.com... > Suppose I have an antenna some distance from the house. I run the > transmission line down from the antenna, bury the line, run it > underground to the house, place a lightning arrestor and ground just > outside the house, then run the transmission line up the side of the > house to the operating position on the second floor. Does anyone see a > problem with this arrangement? I can't imagine that a lightning would > "want" to travel back up toward the operating position when it has a > good ground (at the arrestor) closer to the antenna. > > -JJ > Article: 216734 of rec.radio.amateur.antenna From: "Crazy George" References: <1125432356.646414.257460@o13g2000cwo.googlegroups.com> Subject: Re: Exciter & Transmitter Date: Tue, 30 Aug 2005 21:01:30 -0500 Message-ID: <4315158a_3@news1.prserv.net> Broadcast stations are licensed at various power levels, and indeed, AM stations typically (except clear channel) change power at sunrise and sunset. FM stations are also licensed at various powers, where the antenna height above average terrain and antenna gain also enter into the radiated power equation. So manufacturers design an exciter which provides a set of features desired by some large segment of their target customers, and with that a series of amplifies of different power levels to meet the license parameters. -- Crazy George The attglobal.net address is a SPAM trap. Please change that part to: attbiz properly formatted. "CD" wrote in message news:1125432356.646414.257460@o13g2000cwo.googlegroups.com... > Hey all, > > I've been browsing around looking at AM / FM transmitters and I keep > bumping into exciters. I'm curious. What is the difference between > exciters and transmitters? > > I'm new to broadcasting, so I'm still getting used to the lingo. > > Thanks! > Article: 216735 of rec.radio.amateur.antenna From: W2RAC Subject: Need help to optmise a older Hy-Gain antenna for 2M SSB Message-ID: Date: Wed, 31 Aug 2005 03:44:26 GMT PLEASE, I need help. If anyone can run the numbers, I have tried Quick Yagi with little success. I have a pair of the OLDER Hy-Gain 2m antenna's. There design was a 200ohm (I think) Hairpin match (to 50ohm) with the reflector and directors INSULATED from the boom. Current model for the last 10+ years is the elements are not insulated >from the boom. I want to respace the elements, possilbing cutting down as it is easier than lenghting them, to get the best 1. Beamwith/pattern 2. FB 3. Gain. I am only going to use them on 2M SSB with a center freq of 144.250 Here are the measurments. 14' boom El Lgth Space D6 34.62500 32.25 D5 35.00000 26.75 D4 35.12500 25.75 D3 35.12500 28.25 D2 35.25000 22.25 D1 35.50000 12.75 Driven 32.75000 16.75 Ref 44.37500 1.75 Notes. Measured in Inches. Reflector is mounted 1.75 inch from end of boom, D6 is 1.5 inch from end of boom. All Elements are INSULATED on top of the boom. If needbe I can remove 1 director as the insulator need replacing. Article: 216736 of rec.radio.amateur.antenna From: "Hal Rosser" References: <1125432356.646414.257460@o13g2000cwo.googlegroups.com> Subject: Re: Exciter & Transmitter Message-ID: Date: Tue, 30 Aug 2005 23:59:55 -0400 If its output is to an antenna, then its a transmitter If the output is to an amplifier, then its an exciter. Usually. Article: 216737 of rec.radio.amateur.antenna From: "Hal Rosser" References: <574Re.39$%j7.21@bignews3.bellsouth.net> Subject: Re: Amplfier opinion Message-ID: Date: Wed, 31 Aug 2005 00:18:02 -0400 Most folks use 100 watts or less so you can talk to most people with the same power level or less. Antennas have the ability of amplifying the receiving station's signal to you as well as your signal to them. (gain) building and designing Antennas is a way to learn and and enjoy the hobby. contrary to what some may say, you don't have to be an engineer to enjoy the hobby. If you need the amplifier (like on 80 meters at 9 pm when everyone is trying to claim a freq for an impromptu net) - then its usually less stressful to just switch it off until the band is less busy. Article: 216738 of rec.radio.amateur.antenna From: "Michael Herron" Subject: Dual Band "on glass" antennas, good or bad? Message-ID: Date: Wed, 31 Aug 2005 04:22:53 GMT What do youse guise think of on glass dualband 2/440 antennas? I have never used one but are now considering it as an option rather than drilling a hole in the roof of my new Chev Silverado. An on glass antenna would also be much easier to route the coax with rather than needing to remove the headliner. Anyone out there that was impressed or particularly dissappointed by on glass antenna performance? Any issues with mounting on a window that has the defog element in it? Thanks, Mike K7MH. Article: 216739 of rec.radio.amateur.antenna From: Howard Subject: Re: Dual Band "on glass" antennas, good or bad? Date: Tue, 30 Aug 2005 22:04:58 -0700 Message-ID: References: On Wed, 31 Aug 2005 04:22:53 GMT, "Michael Herron" wrote: >What do youse guise think of on glass dualband 2/440 antennas? I have never >used one but are now considering it as an option rather than drilling a hole >in the roof of my new Chev Silverado. An on glass antenna would also be much >easier to route the coax with rather than needing to remove the headliner. >Anyone out there that was impressed or particularly dissappointed by on >glass antenna performance? Any issues with mounting on a window that has the >defog element in it? Thanks, Mike K7MH. > Used a Larsen 2 meter glass mount and was happy with the performance, no experience with a dual band though. As to mounting it on the defog element - bad idea. Howard Article: 216740 of rec.radio.amateur.antenna Subject: Re: Lightning Question From: Ed References: <1125443164.355999.136830@g47g2000cwa.googlegroups.com> Message-ID: Date: Wed, 31 Aug 2005 05:11:23 GMT > Suppose I have an antenna some distance from the house. I run the > transmission line down from the antenna, bury the line, run it > underground to the house, place a lightning arrestor and ground just > outside the house, then run the transmission line up the side of the > house to the operating position on the second floor. Does anyone see a > problem with this arrangement? I can't imagine that a lightning would > "want" to travel back up toward the operating position when it has a > good ground (at the arrestor) closer to the antenna. Assuming your "ground" system outside the house is fairly substantial, (not just a single rod), then I'd say your system is about as good as it would get..... However, with a direct strike, there is NO guaranty! Even a tiny fraction of a gazillion volts can cause you grief. Best bet, disconnect the coax in a storm, too!. Ed K7AAT Article: 216741 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Looking for help regarding satellie antennae Date: Wed, 31 Aug 2005 01:28:19 -0500 Message-ID: <666-43154E03-1184@storefull-3255.bay.webtv.net> References: Roger, ZR3RC wrote: "These dishes also have very narrow beamwidth making their aiming very precise." You are right. Even an 18-invh dish needs a pretty good elevation angle in the UK to get best reception in the KU band from a satellite parked over the equator. I checked the Direct TV website. A geostationary synchronous bird flys at more than 22 000 miles above the earth`s surface. The horizontal distance is always a fraction of the altitude of the satellite, so the elevation angle for line of sight is substantial no matter what the azimuth. I am still puzzled as to why so many dishes I saw in Scotland were aimed so low. Direct TV gives instructions on how to align a dish in their service. They send an initial elevation angle "tick-mark" setting to the customer. It is then up to him to acquire the bird and optimize setting the dish for best signal. Direct TV has 3 satellites available to the customer, and though they are several degrees apart along the equator, one azimuth setting of the dish is expected to give satisfactory signals from all three. Best regards, Richard Harrison, KB5WZI Article: 216742 of rec.radio.amateur.antenna From: "Jerry Martes" References: <666-43154E03-1184@storefull-3255.bay.webtv.net> Subject: Re: Looking for help regarding satellie antennae Message-ID: Date: Wed, 31 Aug 2005 07:03:13 GMT "Richard Harrison" wrote in message news:666-43154E03-1184@storefull-3255.bay.webtv.net... > Roger, ZR3RC wrote: > "These dishes also have very narrow beamwidth making their aiming very > precise." > > You are right. Even an 18-invh dish needs a pretty good elevation angle > in the UK to get best reception in the KU band from a satellite parked > over the equator. I checked the Direct TV website. A geostationary > synchronous bird flys at more than 22 000 miles above the earth`s > surface. The horizontal distance is always a fraction of the altitude of > the satellite, so the elevation angle for line of sight is substantial > no matter what the azimuth. I am still puzzled as to why so many dishes > I saw in Scotland were aimed so low. > > Direct TV gives instructions on how to align a dish in their service. > They send an initial elevation angle "tick-mark" setting to the > customer. It is then up to him to acquire the bird and optimize setting > the dish for best signal. > > Direct TV has 3 satellites available to the customer, and though they > are several degrees apart along the equator, one azimuth setting of the > dish is expected to give satisfactory signals from all three. > > Best regards, Richard Harrison, KB5WZI Richard This a L band receiver. Their satelites for the ASR WS 201 pump out alot of power with traveling wave tube amplifiers at about 1,400 MHz.. The OP may be on the far edge of the coverage "footprint" from the satellite over Africa so his antenna positioning could be more critical that locations closer to Central Africa. Jerry Article: 216743 of rec.radio.amateur.antenna From: "Dori A Schmetterling" References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116950811.722761.163430@g47g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <43148C75.606@library.berkeley.edu> <1125468910.764550.90420@g49g2000cwa.googlegroups.com> Subject: Re: ENOUGH OF THIS!!! Date: Wed, 31 Aug 2005 11:30:27 +0100 Message-ID: <431586c5$0$13695$cc9e4d1f@news-text.dial.pipex.com> That's exactly what they did. DAS For direct contact replace nospam with schmetterling --- "Steve Carras" wrote in message news:1125468910.764550.90420@g49g2000cwa.googlegroups.com... [...] > > crossopsted > Article: 216744 of rec.radio.amateur.antenna Subject: Re: Power radiated from feedlines From: Cecil Moore Date: Wed, 31 Aug 2005 07:29:58 -0500 Message-ID: <1125491556_1513@spool6-east.superfeed.net> References: dansawyeror wrote: > Below is a link to a site that claims to model coax radiation from a > dipole. > > http://www.smeter.net/feeding/feedpowr.php Please note that the third wire to ground creates the unbalance that causes feedline radiation. You seem to be confusing cause and effect. The cause of the feedline radiation is the existence of that third wire, not SWR. All it proves is that feedline radiation is caused by that third wire path which unbalances the source currents. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- Article: 216745 of rec.radio.amateur.antenna Message-ID: <31303030383738354315B0DF22@zetnet.co.uk> Date: Wed, 31 Aug 2005 13:30:07 +0100 From: Dave Piggin Subject: Antron 99 Hi All. I've still not found the way to seperate the outer caseing from the inner radiating wire, even looking at the web sites photo's and destructions. Originally I thought I'd found the answer, because there was a small blob of solder on the chromed metal collar that I thought terminated the wire, unfortunatly not so. I have removed all the fixing glue from around the collars and expected to be able to remove/seperate it but with no luck. Any of you guys got any pointers before I end up destroying what might be a potential good 10 Mtr antenna. Any body done this project and been successful? The web shots are reasonable to deduce what to do, but attaining it is very different. TIA Dave. -- Amateur Radio Call Sign M1BTI, Located in Manchester England. Locator square IO83TK Chairman Of Trafford Radio Club. Club Call Signs G0TRG & M1BBP Located at Umist, University Of Manchester Institute For Science And Technology Share What You Know, Learn What You Dont. Article: 216746 of rec.radio.amateur.antenna From: "Ken Bessler" Subject: Hey Charlie AD5TH - your tower still standing? Message-ID: Date: Wed, 31 Aug 2005 08:01:38 -0500 -- X-No-Archive: Yes I've noticed that you've not posted here bragging about that P.O.S. tower of yours still standing. I wonder if your silence means Katrina got you? Enquiring minds want to know -- 73 de Ken KGØWX - Flying Pigs #-1055 Elecraft K2 #4913 Article: 216747 of rec.radio.amateur.antenna From: "laborkei" Subject: Amateur Radio Assistance to Katrina Disaster! Message-ID: Date: Wed, 31 Aug 2005 09:48:06 -0400 I have been watching wwltv.com and wdsutv.com on the Internet. I keep hearing about the lack of emergency services to communicate. Does anyone know if any Amateur Operators are being engaged to assist? -- Article: 216748 of rec.radio.amateur.antenna Subject: Re: Amateur Radio Assistance to Katrina Disaster! From: "Dr.Maggot" References: Message-ID: Date: Wed, 31 Aug 2005 14:06:20 GMT "laborkei" wrote in news:JyiRe.2664$xw1.1794 @bignews6.bellsouth.net: > I have been watching wwltv.com and wdsutv.com on the Internet. > I keep hearing about the lack of emergency services to communicate. > Does anyone know if any Amateur Operators are being engaged to assist? > > "WLOX managers suggest the best way to find news of friends and family is through HAM radio operators. There is a HAM radio operator stationed at WLOX; call sign is WX5AAA." No frequencies given: http://www.wlox.com/Global/story.asp?S=3782622 Mike -- "All my friends can't be wrong!" Remember, stupidity runs in herds. Article: 216749 of rec.radio.amateur.antenna From: "Dave" References: Subject: Re: Amplfier opinion Message-ID: Date: Wed, 31 Aug 2005 14:34:04 GMT How does the ALS600 do when using with the Butternut HF9V vertical? "Ham op" wrote in message news:FoadnZHij9SOC4jeRVn-pg@comcast.com... > Dave wrote: > > I am thinking of buying the Ameritron 600 watt solid state amp and was > > wondering what opinions you all may have of it. Thanks > > > > > How many $per watt for the Ameritron 600? Ameritron lists the ALS-600 at > $1299. For base station usage you need the power supply. Total package > list price of $1428. Or, $2.38 per watt [SSB]. [600 watt] > > The AL-811H lists for $799 or $1.00 per watt [SSB]. [800 watt] > > The AL-80B lists for $1349 or $1.39 per watt [SSB]. [1000 watt] > > The AL-1500 lists for $3045 or $2.03 per watt [SSB]. [1500 watt] > > If you are considering base usage the AL-811H is less than 1/2 S unit > below the AL-1500 at about 1/2 the price. > > The ALS-600 is only 1 1/4 S units above a 100 watt base or mobile station. > > I own the AL-80B. It has about 1/4 S unit below the AL-1500. [SSB] > > Save some money and put it to good use on your antenna system. > > Article: 216750 of rec.radio.amateur.antenna From: "Bill KB3GUN" References: Subject: Re: Amateur Radio Assistance to Katrina Disaster! Date: Wed, 31 Aug 2005 10:41:41 -0400 Message-ID: <4315c194$0$50878$ec3e2dad@news.usenetmonster.com> "laborkei" wrote in message news:JyiRe.2664$xw1.1794@bignews6.bellsouth.net... >I have been watching wwltv.com and wdsutv.com on the Internet. > I keep hearing about the lack of emergency services to communicate. > Does anyone know if any Amateur Operators are being engaged to assist? > > Amateur Radio Volunteers Involved in Katrina Recovery NEWINGTON, CT, Aug 30, 2005--Amateur Radio Emergency Service (ARES) volunteers in Louisiana are engaged in the Hurricane Katrina recovery effort, and more are waiting in the wings to help as soon as they can enter storm-ravaged zones. Winds and flooding from the huge storm wreaked havoc in Louisiana, Mississippi and Alabama after Katrina came ashore early Monday, August 29. Louisiana ARES Section Emergency Coordinator Gary Stratton, K5GLS, told ARRL that some 250 ARES members have been working with the Red Cross and the state's Office of Homeland Security Emergency Preparedness. Much of the affected areas remain flooded and dangerous, however. As a result, state officials have not allowed emergency or other units to enter the flooded zones, and there is still no communication with many coastal areas. The West Gulf ARES Emergency Net remains active (7.285 MHz days/3.873 MHz nights), and radio amateurs not involved in emergency communication have been asked to keep these frequencies clear when the net is in session. A high volume of health-and-welfare requests reportedly is slowing the passage of critical tactical and emergency traffic. The Salvation Army Team Emergency Radio Network (SATERN) on 14.265 MHz has been accepting and handling health-and-welfare inquiries on the air and via its Web site. Full text here: http://www.arrl.org/news/stories/2005/08/30/1/?nc=1 73 Article: 216751 of rec.radio.amateur.antenna From: Walter Maxwell Subject: Re: Power radiated from feedlines Message-ID: <4igbh197rop3c0l9b13uj19lokv4lvvtlk@4ax.com> References: Date: Wed, 31 Aug 2005 10:47:15 -0400 On Tue, 30 Aug 2005 20:05:05 -0700, dansawyeror wrote: > >I have tried several parameters and have gotten results from a very low level >with a close match to over 90% of power radiated in the feedline when the dipole >resonance is far from the transmit frequency. > >We may use this model for a couple of things. It is available and it predicts >radiation. That gives the opportunity to create a test. I for one are willing to >experiment. > >Dan Will you please describe the details of your experiment where you claim 90% of the power is radiated from the feedline? How did you make this measurement? Walt, W2DU Article: 216752 of rec.radio.amateur.antenna From: Matthew Weber Subject: Re: ENOUGH OF THIS!!! Date: Wed, 31 Aug 2005 08:16:04 -0700 Message-ID: References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <429f10b1$0$289$cc9e4d1f@news-text.dial.pipex.com> <429f1cad$1_1@spool9-west.superfeed.net> <42a04730$1_2@spool9-west.superfeed.net> <11ha0ptrqj62866@corp.supernews.com> This is a multi-part message in MIME format. --------------030107040705020600000508 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit WCB wrote: >Matthew Weber wrote: > > > >>Cecil Moore wrote: >> >> >> >>>Dave Althoff, Jr. wrote: >>> >>> >>> >>>>Do you believe the Bible to be the "Word of God"? Or the "Words of >>>>God"? >>>> >>>> >>>Actually, the word or words of "Elohim", i.e. Gods. >>>Elohim is *PLURAL*. Yahweh was one of the Elohim. >>> >>> >>Yes, Elohim is a plural word. It doesn't necessarily signify that >>Yahweh is one of many gods. Some grammarians have referred to it as a >>"plural of majesty". >> >> >> > >See Genesis 6, god has a number of sons, >when the bible says gods, plural, it means that literally. > > > How do you figure? That isn't in line with anything found elsewhere in the Bible, or any respectable hermeneutic. Does the Queen of England mean to imply that there is more than one of her when she uses the "royal We"? -- Matthew Weber
Curatorial Assistant
Jean Gray Hargrove Music Library
University of California, Berkeley

Some seeds fell by the way side.
        The Holy Bible (The New Testament):  The Gospel According to St Matthew, 13:4 --------------030107040705020600000508 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit WCB wrote: 
Matthew Weber wrote:

  
Cecil Moore wrote:

    
Dave Althoff, Jr. wrote:

      
Do you believe the Bible to be the "Word of God"?  Or the "Words of
God"?
        
Actually, the word or words of "Elohim", i.e. Gods.
Elohim is *PLURAL*. Yahweh was one of the Elohim.
      
Yes, Elohim is a plural word.  It doesn't necessarily signify that
Yahweh is one of many gods.  Some grammarians have referred to it as a
"plural of majesty".

    
  
See Genesis 6, god has a number of sons, 
when the bible says gods, plural, it means that literally.
How do you figure?  That isn't in line with anything found elsewhere in the Bible, or any respectable hermeneutic.

Does the Queen of England mean to imply that there is more than one of her when she uses the "royal We"?

-- 
<html>
Matthew Weber <br>
Curatorial Assistant<br>
Jean Gray Hargrove Music Library<br>
University of California, Berkeley<br><br>
Some seeds fell by the way side.<br>
<x-tab>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</x-tab>The Holy Bible (The New Testament):&nbsp; <i>The Gospel According to St Matthew, </i>13:4</html>
--------------030107040705020600000508-- Article: 216753 of rec.radio.amateur.antenna From: "Fred W4JLE" References: <4igbh197rop3c0l9b13uj19lokv4lvvtlk@4ax.com> Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 11:24:43 -0400 Message-ID: <82bfc$4315cbbd$97d55b95$22854@ALLTEL.NET> I have to call BS on this one Dan! > On Tue, 30 Aug 2005 20:05:05 -0700, dansawyeror > wrote: > > > > >I have tried several parameters and have gotten results from a very low level > >with a close match to over 90% of power radiated in the feedline when the dipole > >resonance is far from the transmit frequency. > > > >We may use this model for a couple of things. It is available and it predicts > >radiation. That gives the opportunity to create a test. I for one are willing to > >experiment. > > > >Dan > Article: 216754 of rec.radio.amateur.antenna From: "Fred W4JLE" References: Subject: Re: Amateur Radio Assistance to Katrina Disaster! Date: Wed, 31 Aug 2005 11:40:25 -0400 Message-ID: <704c5$4315cf6b$97d55b95$24217@ALLTEL.NET> Here is the latest info that I have: Fred W4JLE DEC SEOC SC The on-the-ground situation in SE Louisiana and SW Mississippi is as bad as television is reporting. Neither state is permitting disaster relief agencies into the affected areas except on a very limited basis and only then where conditions are stable. Nearly everyone is still staging as close by as possible and waiting. The Louisiana SM (Mickey Cox K5MC) and SEC (Gary Stratton K5GLS) are in communications with state officials, who have directed them to NOT advertise for volunteers. Some volunteers have been requested, and these are being staged at the state EOC. The situation for the Mississippi SM and SEC, Malcolm Keown W5XX, in Vicksburg MS is very uncertain. His station is completely on the ground and EchoLink repeaters in the area are off-the-air. Attempts to contact Assistant SMs have been unsuccessful. An AB2M.net Amateur Radio operator registration web site has been setup and is ready to go public when approval is received. Some Amateur Radio operators are known to be traveling towards the affected areas with emergency services and disaster relief agencies as dedicated communications resources. Despite everyone's nearly overwhelming desire to help, about all we can do right now is to make preparations for a prompt response when the officials finally give their approval. None of us know when that will occur. Jerry Reimer, KK5CA South Texas "laborkei" wrote in message news:JyiRe.2664$xw1.1794@bignews6.bellsouth.net... > I have been watching wwltv.com and wdsutv.com on the Internet. > I keep hearing about the lack of emergency services to communicate. > Does anyone know if any Amateur Operators are being engaged to assist? > > > -- > > > Article: 216755 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 10:39:52 -0500 Message-ID: <575-4315CF48-9@storefull-3257.bay.webtv.net> References: Reg, G4FGQ wrote: "Perhaps somebody might be prepared to state the power actually radiated >from feedlines in watts." Someone has. A feedline is a way to get energy from here to there. Usually we want to keep all the energy on or close to the line as it travels and lose as little as possible to radiation and conversion to heat. Terman gives an approximate formula credited to Sterba and Feldman for radiation from a 2-wire nonresonant line, provided that the lengrh is at least 20X the spacing and the spacing is less than 0.1 wavelength: Radiated power/Isquared=160(pi D/lambda)squared. D/lambda is the spacing in wavelengths I is the rms line current. Terman notes that the parallel line radiates 4X the power that a doublet of length equal to the line spacing would, providing that the line and doublet currents are equal. Terman provides a figure to be used to adjust the estimated radiation upwards for longer feedlines (up to 5 wavelengths), and for greater heights (up to 0.5 wavelength above the earth). See 1943 "Radio Engineers` Handbook", page 194. Best regards, Richard Harrison, KB5WZI Article: 216756 of rec.radio.amateur.antenna From: "kegwasher" References: Subject: Re: Amateur Radio Assistance to Katrina Disaster! Date: Wed, 31 Aug 2005 11:52:17 -0400 Message-ID: "laborkei" wrote in message news:JyiRe.2664$xw1.1794@bignews6.bellsouth.net... > I have been watching wwltv.com and wdsutv.com on the Internet. > I keep hearing about the lack of emergency services to communicate. > Does anyone know if any Amateur Operators are being engaged to assist? > The West Gulf ARES Emergency Net remains active (7.285 MHz days/3.873 MHz nights), and radio amateurs not involved in emergency communication have been asked to keep these frequencies clear when the net is in session. (this is an emergency H&W freq) A high volume of health-and-welfare requests reportedly is slowing the passage of critical tactical and emergency traffic. The Salvation Army Team Emergency Radio Network (SATERN) on 14.265 MHz has been accepting and handling general health-and-welfare inquiries on the air and via its Web site. Article: 216757 of rec.radio.amateur.antenna From: your name Subject: BBB Complaint # 414840 against Bozak Antenna Message-ID: Date: Wed, 31 Aug 2005 16:51:58 GMT COMPANY OR ORGANIZATION INFORMATION: Bozak Antenna 8 Timberwick Drive Clifton Park, NY United States 12065 (518)373-8069 http://www.bozak.org http://members.tripod.com/~Bozak/HOMEPAGE.HTM COMPLAINT INFORMATION: Complaint #: 414840 Complaint Type: Company (other than automobile) Date Received: 9/12/2001 Primary Complaint Classification: Credit or Billing Disputes Secondary Complaint Classification: Delivery Issues Complaint: To whom it may concern: Mr. Steve G. Bozak was contacted in mid July 2001 regarding products (eg. antennas and coax cables) which were available for sale from his firm. Mr. Bozak quoted prices and then later changed the quote to reflect higher prices (25% higher) without my authorization. Mr. Bozak concludes that since I gave my credit card info that I agreed in principle with the altered price quote (which I did not agree too). In addition to the order being 2-3 weeks late (because his firm did not have enough coax cable on hand), I then had to follow- up and specifically request a copy of the original billing invoice. When the invoice was finally received in late August, and after noting the higher prices charged, I immediately called and complain to Greg (Bozak's sales rep). Greg was informed that I received a lower price quote in mid July. Greg requested that I forward that quote which I did. After reviewing, Mr. Bozak wrote back on September 12, 2001 that "I am sorry for the confusion about the prices.... every effort has been made so this does not happen." Thus, Mr. Bozak concedes that he (and his organization) screwed up but they want me to eat the higher costs. This is why this matter is being forwarded to your offices for recording and resolution purposes. Prospective customers need to know about Bozak's deplorable customer service/business practices. Article: 216758 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: Hey Charlie AD5TH - your tower still standing? Date: Wed, 31 Aug 2005 11:55:00 -0500 Message-ID: <11hbo7dbbv93k3c@corp.supernews.com> References: Ken Bessler wrote: > -- > X-No-Archive: Yes > > I've noticed that you've not posted here bragging > about that P.O.S. tower of yours still standing. > > I wonder if your silence means Katrina got you? > > Enquiring minds want to know > > -- > 73 de Ken KGØWX - Flying Pigs #-1055 > Elecraft K2 #4913 > > Since he lives about 190 miles NNE of NO my guess is that not only is the TOWER OF UNION MS down, but he lost the trees that were attempting to hold the TOU up. He is most likely out of electricity and telephone (internet connection) lines. If he suffered any damages I do hope for his recovery. Dave WD9BDZ Article: 216759 of rec.radio.amateur.antenna From: richardharrison@webtv.net (Richard Harrison) Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 12:03:04 -0500 Message-ID: <1079-4315E2C8-71@storefull-3252.bay.webtv.net> References: Dan wrote: "We may use this model for a couple of things." Dan attached a posting from Reg, G4FGQ. Reg`s description of the "Centre-Fed Dipole - Radiation from Coaxial Feedline" tells it as it is. About 45 years ago, I (Richard Harrison) worked for a company exploring for oil in the Chaco Jungle of Bolivia. Communications were by HF radio at all sites in the jungle and at offices in Cochabamba and La Paz. Radios were Collins 30K-5 transmitters and 51-J receivers at all locations. All antennas were center-fed 1/2-wave dipoles up only about 1/4-wave due to economics and generally were broadside to some favored direction. The feedline was also about 1/4-wavelength for convenience, but the antennas loaded, took a lot of power and the 30-K finals dipped OK. Soil at the radio sites was mostly sand and didn`t really ground anything very much. The length of the coax presented a high impedance to the outside shield of the coax cable at the dipole, whatever it might have been. At 1/4-wave antenna height, directionality was small and whatever the coax radiated, it likely filled-in any nulls. All stations could clearly hear all others all day, so the operators were satisfied. Much of the radiation was straight up so we likely bebefitted from near vertical incidence propagation. The transmitters shook the aether with their power, but the 51-J has a nice dial but not much else. Nevertheless, everything worked. My previous employer had given away all its 51-J`s, they were so sorry, and replaced them with Hammarland SP-600`s. I didn`t take a 51-J, I was using one of the Super Pro`s. My experience is anecdotal. Best regards, Richard Harrison, KB5WZI Article: 216760 of rec.radio.amateur.antenna From: tclay@qmc.ph.msstate.edu Subject: Re: Hey Charlie AD5TH - your tower still standing? Date: 31 Aug 2005 12:22:35 -0500 Message-ID: <87psru81ic.fsf@qmc.ph.msstate.edu> References: <11hbo7dbbv93k3c@corp.supernews.com> >Since he lives about 190 miles NNE of NO my guess is that not only is >the TOWER OF UNION MS down, but he lost the trees that were attempting >to hold the TOU up. He is most likely out of electricity and telephone >(internet connection) lines. The storm was quite strong even in central MS, probably still category 1 there. Many even "built-by-the-book" towers would be destroyed from there south, especially if trees fell across the guy wires. Here in northeast MS (Starkville) Katrina was at strong tropical storm strength. Several trees in my yard were blown over. Fortunately my two towers (100',70') survived and the only damage was some bent/broken 15m yagi elements from flying tree branches. Tor N4OGW Starkville, MS Article: 216761 of rec.radio.amateur.antenna From: Matthew Weber Subject: Re: ENOUGH OF THIS!!! Date: Wed, 31 Aug 2005 11:21:23 -0700 Message-ID: References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <429f10b1$0$289$cc9e4d1f@news-text.dial.pipex.com> <429f1cad$1_1@spool9-west.superfeed.net> <42a0acff$1_2@spool9-west.superfeed.net> <42a2481a$1_1@spool9-west.superfeed.net> <42a300d1$1_2@spool9-west.superfeed.net> Cecil Moore wrote: > Tony Elka wrote: > >> You do realize that Texas was part of Mexico before we stole it? > > > Texas was actually stolen four or five times and one > time Mexico was the thief when they stole Texas from > Spain. Texas was originally stolen by the Europeans > from the Indians who thought owning land was a ridiculous > concept. And look where that attitude got them! -- Matthew Weber
Curatorial Assistant
Jean Gray Hargrove Music Library
University of California, Berkeley

Some seeds fell by the way side.
        The Holy Bible (The New Testament):  The Gospel According to St Matthew, 13:4 Article: 216762 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 11:46:04 -0700 Message-ID: <11hbung9072oqa1@corp.supernews.com> References: <575-4315CF48-9@storefull-3257.bay.webtv.net> The calculations you quote assume equal and opposite (i.e., purely differential mode) currents in the feedline conductors. The topic under discussion is radiation due to common mode current. Roy Lewallen, W7EL Richard Harrison wrote: > Reg, G4FGQ wrote: > "Perhaps somebody might be prepared to state the power actually radiated > from feedlines in watts." > > Someone has. A feedline is a way to get energy from here to there. > Usually we want to keep all the energy on or close to the line as it > travels and lose as little as possible to radiation and conversion to > heat. > > Terman gives an approximate formula credited to Sterba and Feldman for > radiation from a 2-wire nonresonant line, provided that the lengrh is at > least 20X the spacing and the spacing is less than 0.1 wavelength: > > Radiated power/Isquared=160(pi D/lambda)squared. > > D/lambda is the spacing in wavelengths > > I is the rms line current. > > Terman notes that the parallel line radiates 4X the power that a doublet > of length equal to the line spacing would, providing that the line and > doublet currents are equal. > > Terman provides a figure to be used to adjust the estimated radiation > upwards for longer feedlines (up to 5 wavelengths), and for greater > heights (up to 0.5 wavelength above the earth). > > See 1943 "Radio Engineers` Handbook", page 194. > > Best regards, Richard Harrison, KB5WZI > Article: 216763 of rec.radio.amateur.antenna From: "Percival P. Cassidy" Subject: Re: Amateur Radio Assistance to Katrina Disaster! References: Message-ID: Date: Wed, 31 Aug 2005 14:50:13 -0400 My XYL said she saw/heard Larry King telling people last night that ham radio could be the best way of getting information to and from the affected areas. I have been listening to SATERN on 14.265 handling emergency/H&W traffic. "Perce" (aka Alan NV8A) On 08/31/05 09:48 am laborkei tossed the following ingredients into the ever-growing pot of cybersoup: > I have been watching wwltv.com and wdsutv.com on the Internet. > I keep hearing about the lack of emergency services to communicate. > Does anyone know if any Amateur Operators are being engaged to assist? Article: 216764 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: harmonic filters Date: Wed, 31 Aug 2005 13:29:08 -0700 Message-ID: <11hc4ooiq4rqg3f@corp.supernews.com> References: <1125516775.753516.8850@g49g2000cwa.googlegroups.com> What sort of system are you building? Amateur radio? CB? Pirate AM broadcasting? Roy Lewallen, W7EL CD wrote: > Hello all, > > I was just doing some more reading and came up with a few more > questions. It seems that I failed to take into account adding a > harmonic filter between my antenna and RF amp. However, in regards to > low power transmission (100W), would I still need harmonic filters? > > I saw a design for a 1kW AM system and it had several huge harmonic > filters. I think the total weight was about 60 lbs. I want to keep my > system as small as possible. > > Is there an alternative setup to get rid of the harmonic filters? > > Thanks! > Article: 216765 of rec.radio.amateur.antenna From: "Hal Rosser" References: <31303030383738354315B0DF22@zetnet.co.uk> Subject: Re: Antron 99 Message-ID: <%MoRe.3021$xw1.2337@bignews6.bellsouth.net> Date: Wed, 31 Aug 2005 16:54:57 -0400 Why are you wanting to take it apart ? Its unclear what you want to do. I believe its a sealed unit - and I know it makes a good 10-meter vertical. Hook it up and try it - if it works, then use it - if not then get a new one or use a wire antenna. Its just an end-fed half wave. But the antenna as a package is light-weight, easy to adjust (with the rings), and easy to deploy. That makes it popular - but the hype about a lot of gain is just that - hype. "Dave Piggin" wrote in message news:31303030383738354315B0DF22@zetnet.co.uk... > Hi All. > I've still not found the way to seperate the outer caseing from the > inner radiating wire, even looking at the web sites photo's and > destructions. Originally I thought I'd found the answer, because there > was a small blob of solder on the chromed metal collar that I thought > terminated the wire, unfortunatly not so. I have removed all the fixing > glue from around the collars and expected to be able to remove/seperate > it but with no luck. Any of you guys got any pointers before I end up > destroying what might be a potential good 10 Mtr antenna. Any body done > this project and been successful? The web shots are reasonable to deduce > what to do, but attaining it is very different. TIA Dave. > > -- > Amateur Radio Call Sign M1BTI, Located in Manchester England. > Locator square IO83TK > Chairman Of Trafford Radio Club. Club Call Signs G0TRG & M1BBP > Located at Umist, University Of Manchester Institute For Science And > Technology > Share What You Know, Learn What You Dont. Article: 216766 of rec.radio.amateur.antenna From: "Hal Rosser" References: Subject: Re: Dual Band "on glass" antennas, good or bad? BAD Message-ID: Date: Wed, 31 Aug 2005 16:56:29 -0400 BAD "Michael Herron" wrote in message news:xgaRe.3851$kn4.1241@bgtnsc04-news.ops.worldnet.att.net... > What do youse guise think of on glass dualband 2/440 antennas? I have never > used one but are now considering it as an option rather than drilling a hole > in the roof of my new Chev Silverado. An on glass antenna would also be much > easier to route the coax with rather than needing to remove the headliner. > Anyone out there that was impressed or particularly dissappointed by on > glass antenna performance? Any issues with mounting on a window that has the > defog element in it? Thanks, Mike K7MH. > > Article: 216767 of rec.radio.amateur.antenna From: "Ken Bessler" References: <11hbo7dbbv93k3c@corp.supernews.com> <1125521743.045175.230160@f14g2000cwb.googlegroups.com> Subject: Re: Hey Charlie AD5TH - your tower still standing? Message-ID: Date: Wed, 31 Aug 2005 16:05:14 -0500 X-No-Archive: Yes "Rick Scott" wrote in message news:1125521743.045175.230160@f14g2000cwb.googlegroups.com... > Hope not according to wunderground.com Union MS only recieved wind > gusts of 51mph. > > http://www.wunderground.com/history/airport/KMEI/2005/8/29/DailyHistory.html > > Chart for monday the 29th > > Wind Speed 15 mph / 24 km/h (ENE) > Max Wind Speed 32 mph / 52 km/h > Max Gust Speed 51 mph / 82 km/h > Visibility 5 miles / 8 kilometers If that's true and accurate then where is Charlie posting "Look! Look! You jerks berated my super fine installation and look! Look! It survived a hurricane!!! See the before and after pics!". -- 73 de Ken KGØWX - Flying Pigs #-1055 Elecraft K2 #4913 Article: 216768 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: Hey Charlie AD5TH - your tower still standing? Date: Wed, 31 Aug 2005 16:14:59 -0500 Message-ID: <11hc7eur7jarse1@corp.supernews.com> References: <11hbo7dbbv93k3c@corp.supernews.com> <1125521743.045175.230160@f14g2000cwb.googlegroups.com> Ken Bessler wrote: > X-No-Archive: Yes > > "Rick Scott" wrote in message > news:1125521743.045175.230160@f14g2000cwb.googlegroups.com... > >>Hope not according to wunderground.com Union MS only recieved wind >>gusts of 51mph. >> >>http://www.wunderground.com/history/airport/KMEI/2005/8/29/DailyHistory.html >> >>Chart for monday the 29th >> >>Wind Speed 15 mph / 24 km/h (ENE) >>Max Wind Speed 32 mph / 52 km/h >>Max Gust Speed 51 mph / 82 km/h >>Visibility 5 miles / 8 kilometers > > > > If that's true and accurate then where is Charlie posting > "Look! Look! You jerks berated my super fine installation > and look! Look! It survived a hurricane!!! See the before > and after pics!". > > -- > 73 de Ken KGØWX - Flying Pigs #-1055 > Elecraft K2 #4913 > > Lets not berate the man until it is determined whether he is off the air due to embarrassment or to downed power and phone lines. Remember that much of the state is out of power. Dave WD9BDZ Article: 216769 of rec.radio.amateur.antenna From: "David G. Nagel" Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 16:17:42 -0500 Message-ID: <11hc7jvdh8sv35e@corp.supernews.com> References: <1125491556_1513@spool6-east.superfeed.net> Jerry Martes wrote: > "Cecil Moore" wrote in message > news:1125491556_1513@spool6-east.superfeed.net... > >>dansawyeror wrote: >> >>>Below is a link to a site that claims to model coax radiation from a >>>dipole. >>> >>>http://www.smeter.net/feeding/feedpowr.php >> >>Please note that the third wire to ground creates the unbalance >>that causes feedline radiation. You seem to be confusing cause >>and effect. The cause of the feedline radiation is the existence >>of that third wire, not SWR. All it proves is that feedline >>radiation is caused by that third wire path which unbalances >>the source currents. >>-- >>73, Cecil http://www.qsl.net/w5dxp > > > Cecil > > How wrong would it be to say that the *coax* part of the line doesnt > radiate at all? > I see this as a situation where the *outer shield* of a transmission line > is conducting current that radiates. > It seems that a "balanced" antenna that is comprised of a single > conductor and a L shaped conductor that includes the outer conductor of the > coax, could be fed with a balanced line for modeling. > > Jerry > > What I was taught is that in a properly installed antenna system the coax will not radiate. If the antenna is not properly matched to the coax you get current flow along the outside of the coax shield. Dave WD9BDZ Article: 216770 of rec.radio.amateur.antenna From: "Richard Fry" References: <1125516775.753516.8850@g49g2000cwa.googlegroups.com> <11hc4ooiq4rqg3f@corp.supernews.com> <1125521204.011448.291450@g14g2000cwa.googlegroups.com> Subject: Re: harmonic filters Date: Wed, 31 Aug 2005 16:26:50 -0500 Message-ID: <431620fa_2@newsfeed.slurp.net> "CD" wrote > My concern with the harmonic frequencies is mainly > protecting the transmission system and also not interfere with other > sister stations. From what I've read so far, some harmonic frequencies > might couple to the transmitter input and that can affect the output. The usual mechanism is when the 2nd harmonic of an active transmitter (F1) mixes with the fundamental of a nearby station on F2 to produce an IM product at 2*F1-F2. This can occur in a nonlinear output stage of F1, and harmonic filters normally have no affect on the in-band IM product that is generated. The control is to filter the external fundamental signals from entering F1's output stage via the antenna connection, so they are not present there to generate spurs. > Hmm..also, wouldn't the harmonic filters normally be > part of an antenna tuning unit? It is more closely connected with the harmonic "signature" of a given tx, and so is usually supplied as part of the tx system. The tx OEM has to certify that his tx meets specs for harmonics and spurs, and couldn't do that unless the performance of the filtering network was under his control. RF Visit http://rfry.org for FM transmission system papers. Article: 216771 of rec.radio.amateur.antenna Subject: Re: Power radiated from feedlines From: Cecil Moore Date: Wed, 31 Aug 2005 16:30:25 -0500 Message-ID: <1125523982_199@spool6-east.superfeed.net> References: <1125491556_1513@spool6-east.superfeed.net> <4315B80B.4080106@comcast.net> dansawyeror wrote: > If it is true it proves that a driving a "bad" load can cause the coax > feedline to radiate a significant portion of the feed energy. You need to define "bad load". A "bad load" for unbalanced line is a balanced load, no matter what the impedance. A "bad load" for balanced line is an unbalanced load, no matter what the impedance. The third wire used in the aforementioned software is designed to unbalance the system, no matter what the impedance. To illustrate a balanced system, a fourth wire needs to be added in parallel with and about four inches away from the third wire. Then compare the currents in the third and fourth wires under conditions of changing loads. > I due intend to perform experiments to measure and verify what is > happening and the model. Please feel free to experiment but at least a dozen participants of this newsgroup already know what is happening and have been trying to tell you. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- Article: 216772 of rec.radio.amateur.antenna Subject: Re: Power radiated from feedlines From: Cecil Moore Date: Wed, 31 Aug 2005 16:38:19 -0500 Message-ID: <1125524456_207@spool6-east.superfeed.net> References: <1125491556_1513@spool6-east.superfeed.net> Jerry Martes wrote: > How wrong would it be to say that the *coax* part of the line doesnt > radiate at all? The physical construction of the coax (ideal version) ensures that the inside of the coax doesn't radiate because, for ideal coax, the internal currents are perfectly balanced. Any unbalance in the currents is forced to the outside shield by the laws of physics. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216773 of rec.radio.amateur.antenna Subject: Re: Power radiated from feedlines From: Cecil Moore Date: Wed, 31 Aug 2005 16:46:51 -0500 Message-ID: <1125524968_215@spool6-east.superfeed.net> References: <1125491556_1513@spool6-east.superfeed.net> <11hc7jvdh8sv35e@corp.supernews.com> David G. Nagel wrote: > What I was taught is that in a properly installed antenna system the > coax will not radiate. If the antenna is not properly matched to the > coax you get current flow along the outside of the coax shield. Is "matched" the correct word to use there? A 50 ohm balanced dipole is perfectly "matched" to 50 ohm coax but the feedline will likely radiate. A 50 ohm balanced dipole is not "matched" to 600 ohm balanced line but with proper attention to details the feedline will like not radiate much. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- Article: 216774 of rec.radio.amateur.antenna From: tclay@qmc.ph.msstate.edu Subject: Re: Hey Charlie AD5TH - your tower still standing? Date: 31 Aug 2005 16:42:51 -0500 Message-ID: <874q95hjfo.fsf@qmc.ph.msstate.edu> References: <11hbo7dbbv93k3c@corp.supernews.com> <1125521743.045175.230160@f14g2000cwb.googlegroups.com> >Hope not according to wunderground.com Union MS only recieved wind >gusts of 51mph. > >http://www.wunderground.com/history/airport/KMEI/2005/8/29/DailyHistory.html > >Chart for monday the 29th The winds I'm sure were stronger than that. Note the station stopped recording (broken?) at 1pm. They probably saw much higher wind speeds. Even up at Tupelo (substitute KTUP in above URL) there was a gust of 53 mph recorded. Also try Birmingham BHM, which is quite a ways to the east. Tor Article: 216775 of rec.radio.amateur.antenna From: "Caveat Lector" Subject: RE: Amplifier Opinion Message-ID: Date: Wed, 31 Aug 2005 14:58:47 -0700 > Someone wrote "You don't need a linear unless you're on 80 meters - then > you really need a > biggie" Agree and disagree For example, let's start with a 100-Watt exciter then add an afterburner of 800 Watts. Doubling power is 3 dB and an S-unit is 6dB. So from 100W to 200W is 3dB, 200W to 400W is 3 more dB, and 400W to 800W is 3 more dB for a total of 9 dB or only 1-1/2 S-Units possible increase on the receiving end. One can achieve almost the same result with a 3-element beam. BUT Although one and a half S-Units does give a little more oomph while working a pileup, it really comes into play for weak signal work where if it gets you just up out of the noise on the receiving end, two way QSO's may be possible where without the linear, the DX just can't copy. I can attest to this many times on any band. On the other hand I have worked DXCC - QRP - 5 Watts A lot depends on propagation (of course) -- CL -- I doubt, therefore I might be ! Article: 216776 of rec.radio.amateur.antenna From: "Jerry Martes" References: <1125491556_1513@spool6-east.superfeed.net> <11hc7jvdh8sv35e@corp.supernews.com> Subject: Re: Power radiated from feedlines Message-ID: <0OpRe.31498$yv2.4098@trnddc04> Date: Wed, 31 Aug 2005 22:02:36 GMT "David G. Nagel" wrote in message news:11hc7jvdh8sv35e@corp.supernews.com... > Jerry Martes wrote: > >> "Cecil Moore" wrote in message >> news:1125491556_1513@spool6-east.superfeed.net... >> >>>dansawyeror wrote: >>> >>>>Below is a link to a site that claims to model coax radiation from a >>>>dipole. >>>> >>>>http://www.smeter.net/feeding/feedpowr.php >>> >>>Please note that the third wire to ground creates the unbalance >>>that causes feedline radiation. You seem to be confusing cause >>>and effect. The cause of the feedline radiation is the existence >>>of that third wire, not SWR. All it proves is that feedline >>>radiation is caused by that third wire path which unbalances >>>the source currents. >>>-- >>>73, Cecil http://www.qsl.net/w5dxp >> >> >> Cecil >> >> How wrong would it be to say that the *coax* part of the line doesnt >> radiate at all? >> I see this as a situation where the *outer shield* of a transmission >> line is conducting current that radiates. >> It seems that a "balanced" antenna that is comprised of a single >> conductor and a L shaped conductor that includes the outer conductor of >> the coax, could be fed with a balanced line for modeling. >> >> Jerry > What I was taught is that in a properly installed antenna system the coax > will not radiate. If the antenna is not properly matched to the coax you > get current flow along the outside of the coax shield. > > Dave WD9BDZ Dave I'd agree with your statement if "matched" doesnt refer to *impedance* match. Jerry Article: 216777 of rec.radio.amateur.antenna From: "Jerry Martes" References: <1125491556_1513@spool6-east.superfeed.net> <1125524456_207@spool6-east.superfeed.net> Subject: Re: Power radiated from feedlines Message-ID: Date: Wed, 31 Aug 2005 22:07:34 GMT "Cecil Moore" wrote in message news:1125524456_207@spool6-east.superfeed.net... > Jerry Martes wrote: >> How wrong would it be to say that the *coax* part of the line doesnt >> radiate at all? > > The physical construction of the coax (ideal version) ensures > that the inside of the coax doesn't radiate because, for > ideal coax, the internal currents are perfectly balanced. > Any unbalance in the currents is forced to the outside shield > by the laws of physics. > -- > 73, Cecil http://www.qsl.net/w5dxp Cecil I failed to emphisze that any current on the outside of a coaxial transmission line are out of the bounds of the defination of Coax. Jerry Article: 216778 of rec.radio.amateur.antenna From: "Dan/W4NTI" References: Subject: Re: Amateur Radio Assistance to Katrina Disaster! Message-ID: Date: Wed, 31 Aug 2005 22:59:58 GMT "kegwasher" wrote in message news:c7dfb$4315d2f5$d1cc4914$21578@snip.allthenewsgroups.com... > > "laborkei" wrote in message > news:JyiRe.2664$xw1.1794@bignews6.bellsouth.net... >> I have been watching wwltv.com and wdsutv.com on the Internet. >> I keep hearing about the lack of emergency services to communicate. >> Does anyone know if any Amateur Operators are being engaged to assist? >> > > The West Gulf ARES Emergency Net remains active (7.285 MHz days/3.873 MHz > nights), and radio amateurs not involved in emergency communication have > been asked to keep these frequencies clear when the net is in session. > (this is an emergency H&W freq) > > A high volume of health-and-welfare requests reportedly is slowing the > passage of critical tactical and emergency traffic. The Salvation Army > Team > Emergency Radio Network (SATERN) on 14.265 MHz has been accepting and > handling general health-and-welfare inquiries on the air and via its Web > site. > I was able to pass a Emergency message via the SATERN net on 14.265 . A station in the area was able to relay it via the Coast Guard. Ham radio is alive and well. Dan/W4NTI Article: 216779 of rec.radio.amateur.antenna From: "Ralph Mowery" References: Subject: Re: Amplifier Opinion Message-ID: Date: Wed, 31 Aug 2005 23:10:01 GMT "Caveat Lector" wrote in message news:sKpRe.1982$mH.1643@fed1read07... > > Someone wrote "You don't need a linear unless you're on 80 meters - then > > you really need a > > biggie" > > > Agree and disagree > > For example, let's start with a 100-Watt exciter then add an afterburner of > 800 Watts. Doubling power is 3 dB and an S-unit is 6dB. So from 100W to 200W > is 3dB, 200W to 400W is 3 more dB, and 400W to 800W is 3 more dB for a total > of 9 dB or only 1-1/2 S-Units possible increase on the receiving end. One > can achieve almost the same result with a 3-element beam. > > Not many can put up a 3 element beam for 80 meters, 40 meters either. Even a rotatable dipole is not an option for most on 80. The amplifier will sit on the same desk as the rig in most cases. Granted it will not do anything for my receive. I don't use my amp very much. It did come in handy as I was talking to a portable station last Sunday morning on 80 meters. He had a bunch of static and qrm (Shelby hamfest was where he was at) and by me running an amp I could get over the local noise he had. Article: 216780 of rec.radio.amateur.antenna From: Bill Putney Subject: Re: ENOUGH OF THIS!!! Date: Wed, 31 Aug 2005 18:42:27 -0400 Message-ID: References: <1116948846.845758.269720@g49g2000cwa.googlegroups.com> <1116956452.889209.81740@g47g2000cwa.googlegroups.com> <4293acf2$0$298$cc9e4d1f@news-text.dial.pipex.com> <4293be22$1_2@spool9-west.superfeed.net> <1117690429.916477.190610@f14g2000cwb.googlegroups.com> <429f04f7$1_2@spool9-west.superfeed.net> <429f10b1$0$289$cc9e4d1f@news-text.dial.pipex.com> <429f1cad$1_1@spool9-west.superfeed.net> <42a0acff$1_2@spool9-west.superfeed.net> <42a2481a$1_1@spool9-west.superfeed.net> <42a300d1$1_2@spool9-west.superfeed.net> Matthew Weber wrote: > Cecil Moore wrote: > >> Tony Elka wrote: >> >>> You do realize that Texas was part of Mexico before we stole it? >> >> >> >> Texas was actually stolen four or five times and one >> time Mexico was the thief when they stole Texas from >> Spain. Texas was originally stolen by the Europeans >> from the Indians who thought owning land was a ridiculous >> concept. > > > And look where that attitude got them! I've always been puzzled why people thought that how things end up was a surprise. If you took someone who somehow was not aware of the history and said to them: You've got two societies of people on the same land: One group does not believe in private property ownership, and the other one does - which one do you think over time will end up taking posession of and claiming - how else can you put it? - *ownership* of that land? I'm not saying it's right, or that how it was done was right, but I often question the honesty and intelligence of people that act appalled at how it ended up. I mean - it should be a required question on any intelligence test, and anyone who anwered that the group that didn't believe in private property ownership would end up displacing the group that did should be put in the moron category regardless of how they answered any other questions. Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x') Article: 216781 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Amplifier Opinion Date: Wed, 31 Aug 2005 16:24:17 -0700 Message-ID: <11hcf15p65hrhae@corp.supernews.com> References: Just don't make the common mistake of thinking that the units on your receiver's S meter are 6 dB. That can lead to some extremely mistaken conclusions. Hams keep insisting that an "S-unit" is 6 dB, while the marks on typical S-meters almost never are, and sometimes are much different (< 2 dB for example). Roy Lewallen, W7EL Caveat Lector wrote: > > Agree and disagree > > For example, let's start with a 100-Watt exciter then add an afterburner of > 800 Watts. Doubling power is 3 dB and an S-unit is 6dB. So from 100W to 200W > is 3dB, 200W to 400W is 3 more dB, and 400W to 800W is 3 more dB for a total > of 9 dB or only 1-1/2 S-Units possible increase on the receiving end. One > can achieve almost the same result with a 3-element beam. > > BUT Although one and a half S-Units does give a little more oomph while > working a pileup, it really comes into play for weak signal work where if it > gets you just up out of the noise on the receiving end, two way QSO's may be > possible where without the linear, the DX just can't copy. I can attest to > this many times on any band. > > > > On the other hand I have worked DXCC - QRP - 5 Watts > > > > A lot depends on propagation (of course) > Article: 216782 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Amplfier opinion Date: Wed, 31 Aug 2005 16:40:47 -0700 Message-ID: <11hcg03g584vv7f@corp.supernews.com> References: Here's another posting referring to 6 dB "S-units". Have you actually measured how many dB between marks on your receiver's S meter? I have. Here's what they are, on my Icom IC-730, 40 meters, preamp off: S1-S2: 1.4 dB S2-S3: 1.3 dB S3-S4: 1.6 dB S4-S5: 2.3 dB S5-S6: 1.8 dB S6-S7: 3.2 dB S7-S8: 3.1 dB S8-S9: 4.0 dB S9 - S9+10 dB: 5.6 dB S9+10 - S9+20: 7.3 dB S9+20 - S9+30: 6.6 dB S9+30 - S9+40: 10.5 dB S9+40 - S9+50: 11.3 dB S9+50 - S9+60: 13.5 dB So if I put up an antenna with 7 dB gain over a dipole (about par for a 3 element Yagi), it would kick my S meter from S2 to S6 when switching >from the dipole to the Yagi. If I assumed my "S units" were 6 dB, I'd conclude my antenna had 24 dB gain. I'd be mistaken by a factor of 50 -- that is, I'd think my antenna had the gain of an array of about 50 Yagis. I don't understand why we need a 6 dB unit which doesn't bear any fixed relationship to the marks on an S meter. Why not just use dB? Most hams can't measure 6 dB "S units" any better than they can measure dB. I've got it. When somebody asks for a signal comparison and it's a 7 dB difference, I'll just tell him "My S meter went from S2 to S6, which is a difference of 1.2 S units." Everyone should understand that, right? Roy Lewallen, W7EL Ham op wrote: > 7.78 Db BETTER [+1 1/4 S unit] than 100 watts. > > Upgrade the vertical to a beam and the net gain can be as high as +19.78 > dB [3+ S units] on the path: > 1] + 6 dB in receive > 2] + 6 dB in transmit > 3] + 7.78 dB for the amplifier. > > For $1400, a beam has a much better return on investment than an > amplifier by itself. > > The #1 rule I teach new or aspiring hams is "Your station efficiency, > and your enjoyment, is directly proportional to your antenna." > > > > Dave wrote: > >> How does the ALS600 do when using with the Butternut HF9V vertical? >> >> >> "Ham op" wrote in message >> news:FoadnZHij9SOC4jeRVn-pg@comcast.com... >> >>> Dave wrote: >>> >>>> I am thinking of buying the Ameritron 600 watt solid state amp and was >>>> wondering what opinions you all may have of it. Thanks >>>> >>>> >>> >>> How many $per watt for the Ameritron 600? Ameritron lists the ALS-600 at >>> $1299. For base station usage you need the power supply. Total package >>> list price of $1428. Or, $2.38 per watt [SSB]. [600 watt] >>> >>> The AL-811H lists for $799 or $1.00 per watt [SSB]. [800 watt] >>> >>> The AL-80B lists for $1349 or $1.39 per watt [SSB]. [1000 watt] >>> >>> The AL-1500 lists for $3045 or $2.03 per watt [SSB]. [1500 watt] >>> >>> If you are considering base usage the AL-811H is less than 1/2 S unit >>> below the AL-1500 at about 1/2 the price. >>> >>> The ALS-600 is only 1 1/4 S units above a 100 watt base or mobile >>> station. >>> >>> I own the AL-80B. It has about 1/4 S unit below the AL-1500. [SSB] >>> >>> Save some money and put it to good use on your antenna system. >>> >>> >> >> >> > Article: 216783 of rec.radio.amateur.antenna From: ml Subject: Re: Lightning Question References: <1125443164.355999.136830@g47g2000cwa.googlegroups.com> <43151589_3@news1.prserv.net> Message-ID: Date: Wed, 31 Aug 2005 23:49:00 GMT In article <43151589_3@news1.prserv.net>, "Crazy George" wrote: > There is one additional step which seems, from many anecdotal references, to > provide further help. Somewhere along the > cable route, run the coax through at least two sections of steel electrical > conduit. Size immaterial, and grounding > optional. And they need not be connected together. Theories about why this > works run from it forms a lossy coax for > the lightning induced wave on the outside, to impedance mismatch on the > outside to eddy current losses in the steel. > Whatever the mechanism, I know of several locations where it seems to have > reduced the damage from continuing lightning > strikes. And it is certainly cheap enough to include. > > -- > Crazy George > The attglobal.net address is a SPAM trap. Please change that part to: > attbiz properly formatted. > > wrote in message > news:1125443164.355999.136830@g47g2000cwa.googlegroups.com... > > Suppose I have an antenna some distance from the house. I run the > > transmission line down from the antenna, bury the line, run it > > underground to the house, place a lightning arrestor and ground just > > outside the house, then run the transmission line up the side of the > > house to the operating position on the second floor. Does anyone see a > > problem with this arrangement? I can't imagine that a lightning would > > "want" to travel back up toward the operating position when it has a > > good ground (at the arrestor) closer to the antenna. > > > > -JJ > > i wonder if anyone did any actual research on adding some pipe sections?? wonder if that would woork? i'd also recomend some good lightning surperssors such as those made by ice they seem about the best Article: 216784 of rec.radio.amateur.antenna From: "W4WNT" References: Subject: Re: Amateur Radio Assistance to Katrina Disaster! Message-ID: Date: Wed, 31 Aug 2005 23:59:18 GMT Check the ARRL website. No one is going in, but plans are being made for access when possible. Bill, W4WNT "laborkei" wrote in message news:JyiRe.2664$xw1.1794@bignews6.bellsouth.net... >I have been watching wwltv.com and wdsutv.com on the Internet. > I keep hearing about the lack of emergency services to communicate. > Does anyone know if any Amateur Operators are being engaged to assist? > > > -- > > > Article: 216785 of rec.radio.amateur.antenna From: "Reg Edwards" Subject: There are 3 coaxial conductors. Date: Wed, 31 Aug 2005 23:59:51 +0000 (UTC) Message-ID: Dear all, For coaxial cable, at HF, where skin depth is less than the physical outer conductor thickness, there are 3 conductors. Conductor (1) = Outer surface of inner conductor. Conductor (2) = Inside surface of outer conductor. Conductor (3) = Outer surface of outer conductor. The return path for (3) is the remainder of the universe. It behaves as a single conductor transmission line which has calculable Zo and attenuation. (To keep Lord Kelvin happy). When current flows on it, it also has a radiation resistance. The currents in (1) and (2) are always equal and opposite in direction to each other. They are mutually coupled to each other by line inductance and capacitance. The current on (3) is always independent of what flows in (1) and (2) because no mutual coupling exists between them. However, external coupling can occur and be deliberately or accidently induced at the ends of the cable. Any current which finds its way on to (3), which ought to flow in the antenna, will result in the coax participating in the radiation pattern of the whole antenna structure. BUT IT IS A SILLY QUESTION TO ASK HOW MANY WATTS ARE RADIATED FROM THE FEEDLINE. OR, CONVERSELY, HOW MANY MICROWATTS ARE PICKED UP BY THE FEEDLINE ON RECEIVE. The feedline cannot be treated in isolation as if it behaves independently of the antenna. For starters, the radiation resistances of the feedline and antenna do not add arithmetically. They interact with each other. In summary, in your own language, the watts radiated from the coaxial feedline to a resonant 1/2-wave dipole, without a choke balun, can be forgotten about. There may even be a small advantage. Nothing is wasted where there are pigs. ---- Reg, G4FGQ Article: 216786 of rec.radio.amateur.antenna From: Roy Lewallen Subject: Re: Power radiated from feedlines Date: Wed, 31 Aug 2005 17:10:00 -0700 Message-ID: <11hchmsi55e5hc6@corp.supernews.com> References: <1125491556_1513@spool6-east.superfeed.net> <11hc7jvdh8sv35e@corp.supernews.com> Ham op wrote: > > A balanced antenna fed with balanced line, and the line goes away from > the antenna perpendicular [90 degrees angle] for a minimum of 1/4 > wavelength is a properly installed antenna system: [line has minimum or > no radiation] The line will have minimum or no radiation only if fed at the transmitter end with a balanced feed. An unbalanced feed will create unequal currents in the conductors, resulting in radiation. A symmetrical (e.g., twinlead) line doesn't assure balance (equal and opposite currents in the two conductors), and an unbalanced line will radiate, regardless of its physical construction. > A balanced antenna fed with balanced line, and the line goes away from > the antenna non-perpendicular [other than 90 degrees angle] for a > minimum of 1/4 wavelength is an improperly installed antenna system: > [line will radiate] True for both symmetrical line and coax. Radiation is due to common mode current induced on the line. It can be reduced by inserting "current baluns" (common mode chokes) in the line. A couple spaced about a quarter wavelength apart are usually adequate. > A balanced antenna fed with un-balanced line, and the line goes away > from the antenna perpendicular [90 degrees angle] for a minimum of 1/4 > wavelength is an improperly installed antenna system: [line will radiate] The amount of common mode current and therefore radiation depends on the length of the path along the outside of the coax to ground. A current balun (common mode choke) at the feedpoint will reduce the current and therefore radiation. > A balanced antenna fed with un-balanced line, and the line goes away > from the antenna non-perpendicular [other than 90 degrees angle] for a > minimum of 1/4 wavelength is an improperly installed antenna system: > [line will radiate] This is due to induced common mode current. The mechanism is identical to that when a symmetrical line is used. > A balanced antenna fed with un-balanced line and a properly installed > balun, and the line goes away from the antenna perpendicular [90 degrees > angle] for a minimum of 1/4 wavelength is a properly installed antenna > system: [line has minimum or no radiation]. Correct. A current balun at the feedpoint reduces the conducted common mode current. Induced common mode current is prevented by symmetrical feedline placement. > An un-balanced antenna fed with balanced line is an improperly installed > antenna and the line will radiate. Coax feeding an unbalanced antenna will radiate just as much as twinlead feeding an unbalanced antenna. > > NEED I CONTINUE?? A lot of people have learned a list of handy rules like this without having much of an understanding of where they came from or under what circumstances they do and don't apply. For anyone interested in learning more about common mode current, feedline radiation, types of feedlines, and feedline radiation, I suggest taking a look at http://eznec.com/Amateur/Articles/Baluns.pdf. It deals only with conducted common mode current and doesn't discuss induced common mode current -- I'll try to get together a supplement covering that topic when I have time. There was some discussion on this newsgroup not long ago about induced common mode current, but I can't locate the topic right off. It should be possible to find it with a google search. Be sure to also look at the work by Walt Maxwell, W2DU referenced at the end of the balun article. Roy Lewallen, W7EL Article: 216787 of rec.radio.amateur.antenna Subject: Re: Amateur Radio Assistance to Katrina Disaster! From: Greg Message-ID: References: Date: Thu, 01 Sep 2005 00:32:16 GMT > From: "kegwasher" > Organization: none > Reply-To: "kegwasher" > Newsgroups: > rec.radio.amateur.antenna,rec.radio.amateur.digital.misc,rec.radio.amateur.equ > ipment,rec.radio.amateur.misc,rec.radio.amateur.swap,rec.radio.shortwave > Date: Wed, 31 Aug 2005 11:52:17 -0400 > Subject: Re: Amateur Radio Assistance to Katrina Disaster! > > > "laborkei" wrote in message > news:JyiRe.2664$xw1.1794@bignews6.bellsouth.net... >> I have been watching wwltv.com and wdsutv.com on the Internet. >> I keep hearing about the lack of emergency services to communicate. >> Does anyone know if any Amateur Operators are being engaged to assist? >> > > The West Gulf ARES Emergency Net remains active (7.285 MHz days/3.873 MHz > nights), and radio amateurs not involved in emergency communication have > been asked to keep these frequencies clear when the net is in session. > (this is an emergency H&W freq) > > A high volume of health-and-welfare requests reportedly is slowing the > passage of critical tactical and emergency traffic. The Salvation Army Team > Emergency Radio Network (SATERN) on 14.265 MHz has been accepting and > handling general health-and-welfare inquiries on the air and via its Web > site. > There's also a health & welfare net on 3.935 LSB, Louisiana based, I think. Greg Article: 216788 of rec.radio.amateur.antenna From: "Jerry Martes" References: <666-43154E03-1184@storefull-3255.bay.webtv.net> Subject: Re: Looking for help regarding satellie antennae Message-ID: Date: Thu, 01 Sep 2005 02:21:41 GMT "Richard Harrison" wrote in message news:666-43154E03-1184@storefull-3255.bay.webtv.net... > Roger, ZR3RC wrote: > "These dishes also have very narrow beamwidth making their aiming very > precise." > > You are right. Even an 18-invh dish needs a pretty good elevation angle > in the UK to get best reception in the KU band from a satellite parked > over the equator. I checked the Direct TV website. A geostationary > synchronous bird flys at more than 22 000 miles above the earth`s > surface. The horizontal distance is always a fraction of the altitude of > the satellite, so the elevation angle for line of sight is substantial > no matter what the azimuth. I am still puzzled as to why so many dishes > I saw in Scotland were aimed so low. > >> >> > Best regards, Richard Harrison, KB5WZI Richard I suspect that you have confused yourself about the distance and elevation angle to satellites. I'm sure you can clear up the situation if you consider the distance to the geostationary satellite 22,300 miles above the equator when it is viewed from somewhere near the North or South Pole. Jerry