Article: 52367 of rec.radio.amateur.digital.misc From: "Marty Albert" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <9cadnZ5Xf5xbdRffRVn-ow@comcast.com> Subject: Re: Amazing Message-ID: Date: Thu, 19 May 2005 04:26:05 GMT As I recall, at 23 cm and 80 Mbps we had an effective bandwidth of around 100 KHz on the "final" design... That design incorporated TDM, limited SS, and WDM of the signals. Obviously, with multiple forms of simultaneous multiplexing, the bandwidth would through the roof, most likely to around 100-150 MHz. Today, we could use TDM, WDM, SDM, high-end SS, and a few other tricks and, assuming a target data-rate of 100 Mbps, get the on air bandwidth down to around 50-75 KHz, maybe even a little less. With a similar set up except for a target data-rate of 10 Gbps, my back-of-the-envelope calculations are coming up with an on air bandwidth on the order of 30-50 MHz. There may be as much as a 10-15% decrease in bandwidth by using a well designed DSP. Essentially we would need to look carefully at the Ethernet 10+ Gbps over copper and copy those concepts... I have my upper division and grad students looking at ways to do just that.I am hoping in the next month or so, I can reach an agreement with EE department and the RF engineering department to bring in some of their students to help out with those aspects... My students have already found one thing... BASIC Stamps and PIC processors will only work up to about 115 Mbps. Beyond that, they are just too slow. Take Care & 73 -- >From The Desk Of Marty Albert, KC6UFM "Dana H. Myers" wrote in message news:9cadnZ5Xf5xbdRffRVn-ow@comcast.com... > What was the on-the-air bandwidth of Frank's 80Mbps signal? > > Dana K6JQ Article: 52376 of rec.radio.amateur.digital.misc Message-ID: From: news Subject: Re: Amazing References: Date: Thu, 19 May 2005 18:34:31 GMT In message , Hank Oredson writes >So do it! >WiFi gear getting cheap, run it within the ham band. >Works fine. > Hank (or anyone else), Can you point me to reflectors/forums for WiFi ham band networks? I would like to catch up with what people are doing in this area. 73 Ian, G3NRW g3nrw@yahoo.co.uk Article: 52377 of rec.radio.amateur.digital.misc From: "helmsman@mindspring.com" Subject: Dell Dimension 4100/ ts-450-s/Rascal Message-ID: <9e2q81l097gikrj7ebv2r69n789pg78l2s@4ax.com> Date: Thu, 19 May 2005 21:50:13 GMT Any one running this combination? Dell Dimension 4100/ ts-450-s/Rascal Article: 52378 of rec.radio.amateur.digital.misc Message-ID: From: news Subject: Re: Amazing References: Date: Fri, 20 May 2005 08:19:38 GMT In message , Hank Oredson writes >You just hook it up ... totally simple. >Might want an amplifier and good antenna. >Took me about 3 minutes to get a WiFi link running here. >It was between two packet BBS nodes (running SNOS) >and two Windows machines. "It just works." > Yup, I can see that, but it's the "amplifier and good antenna" bit that I'm particularly interested in. What do people use? URLs? 73 Ian, G3NRW g3nrw@yahoo.co.uk Article: 52379 of rec.radio.amateur.digital.misc From: "Charles Brabham" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1116443262.845591.277680@g49g2000cwa.googlegroups.com> Subject: Re: Amazing Message-ID: Date: Fri, 20 May 2005 12:34:18 GMT "news" wrote in message news:hBcHirKzvNjCFwe7@care4free.net... > > > Can you point me to reflectors/forums for WiFi ham band networks? I would > like to catch up with what people are doing in this area. I can give an overview of what's being accomplished in this area... Summary: Lots of hot air, accompanied by little or no action. As far as I can tell, nobody has utilized the WIFI/SHF stuff in a substantial way. There are lots of "mini-networks" here and there, but I have yet to hear about anything of an established, permanent nature that "rings a metroplolis" or even a small town. Another common networking task that has gone unreported is linking packet nets in two cities via WIFI/SHF links. Nobody has stepped forward to even claim to have accomplished that basic task. The ARRL HSMM group has been around for years and years now - but there is no substantial WIFI/SHF amateur radio network - anywhere - to show for it. The same applies to the dozens of WIFI/SHF reflectors and forums that have popped up over the last decade. Lots of speculation and nit-picking technical arguement - but no usable network. ( On any substantial scale. ) There is really no particular reason why these things could not be done. It is all well within the realm of possibility, but for some reason there has been no particular effort to utilize WIFI/SHF equipment for these basic networking applications, except on a small, local scale. I've noted that even the small LANs that pop up from time to time utilizing WIFI/SHF gear seldom stay in operation for very long. Why? - My explanation for this is that the same amateurs who tend to be interested in WIFI also tend to disparage the idea of established amateur radio digital networking. - They all appear to believe that we would be a lot better off to just use the Internet instead of building independent amateur radio infrastructure. - So they don't do it. Charles Brabham, N5PVL Director: USPacket http://www.uspacket.org Admin: HamBlog.Com http://www.hamblog.com Webmaster: HamPoll.Com http://www.hampoll.com Weblog: http://www.hamblog.com/blog_n5pvl.php Article: 52380 of rec.radio.amateur.digital.misc From: Paul Rubin Subject: Re: Amazing References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1116443262.845591.277680@g49g2000cwa.googlegroups.com> Date: 20 May 2005 07:05:21 -0700 Message-ID: <7xhdgyxaam.fsf@ruckus.brouhaha.com> "Charles Brabham" writes: > Why? - My explanation for this is that the same amateurs who tend to be > interested in WIFI also tend to disparage the idea of established amateur > radio digital networking. - They all appear to believe that we would be a > lot better off to just use the Internet instead of building independent > amateur radio infrastructure. - So they don't do it. It could also be that they're more interested in low-speed DX networks than local wifi-like networks. Wifi works perfectly well on part 15 with no licenses needed. Why bother with a licensed version of the same thing? And how do you re-tune the wifi cards to ham bands anyway? Article: 52381 of rec.radio.amateur.digital.misc From: "Hank Oredson" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1116443262.845591.277680@g49g2000cwa.googlegroups.com> Subject: Re: Amazing Message-ID: Date: Fri, 20 May 2005 14:29:35 GMT "Charles Brabham" wrote in message news:ePkje.2363$VB6.2154@newssvr12.news.prodigy.com... > > "news" wrote in message > news:hBcHirKzvNjCFwe7@care4free.net... >> >> >> Can you point me to reflectors/forums for WiFi ham band networks? I would >> like to catch up with what people are doing in this area. > > I can give an overview of what's being accomplished in this area... > > Summary: Lots of hot air, accompanied by little or no action. We have done some test links, to verify path issues. Then we did the cost analysis. About $2k per endpoint for the paths we need to cover. So we have some short links, but any interesting links require investment from a group of hams instead of a single ham. That has not happened. > As far as I can tell, nobody has utilized the WIFI/SHF stuff in a > substantial way. There are lots of "mini-networks" here and there, but I > have yet to hear about anything of an established, permanent nature that > "rings a metroplolis" or even a small town. Another common networking task > that has gone unreported is linking packet nets in two cities via WIFI/SHF > links. Nobody has stepped forward to even claim to have accomplished that > basic task. The problem is cost. > The ARRL HSMM group has been around for years and years now - but there is > no substantial WIFI/SHF amateur radio network - anywhere - to show for it. > > The same applies to the dozens of WIFI/SHF reflectors and forums that have > popped up over the last decade. > > Lots of speculation and nit-picking technical arguement - but no usable > network. ( On any substantial scale. ) The technical issues are simple to solve, they just involve money to buy amplifiers, coax, antennas. The money issue cannot be solved. > There is really no particular reason why these things could not be done. > It is all well within the realm of possibility, but for some reason there > has been no particular effort to utilize WIFI/SHF equipment for these > basic networking applications, except on a small, local scale. I've noted > that even the small LANs that pop up from time to time utilizing WIFI/SHF > gear seldom stay in operation for very long. It's money. > Why? - My explanation for this is that the same amateurs who tend to be > interested in WIFI also tend to disparage the idea of established amateur > radio digital networking. - They all appear to believe that we would be a > lot better off to just use the Internet instead of building independent > amateur radio infrastructure. - So they don't do it. That has not happened here. We just don't have the money to do it. Note that the Portland Metro area is broken up by many large and small hills. We need at least two dozen sites to cover the whole area. At a few $k per site we are talking total investment greater than $50,000. We have had 9600 in place for years, but those sites will mostly not work for WiFi. Think "wet trees". -- ... Hank http://home.earthlink.net/~horedson http://home.earthlink.net/~w0rli Article: 52382 of rec.radio.amateur.digital.misc From: Paul Rubin Subject: Re: Amazing References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <9cadnZ5Xf5xbdRffRVn-ow@comcast.com> Date: 20 May 2005 17:09:47 -0700 Message-ID: <7x3bshjv78.fsf@ruckus.brouhaha.com> "Marty Albert" writes: > You are 100% correct... I may very well a few decimal places off... The > mathematical models show that 100 Mbps should be possible in as little as 10 > KHz. Yes, you are a few decimal places off, but in the wrong direction ;-). Article: 52383 of rec.radio.amateur.digital.misc From: "Marty Albert" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1dsq81dg3pa3lngg121u8gaj2gij1m4eim@4ax.com> Subject: Re: Amazing Message-ID: Date: Sat, 21 May 2005 00:10:46 GMT Amen to that, Hank... -- >From The Desk Of Marty Albert, KC6UFM "Hank Oredson" wrote in message news:Qymje.155$oT1.8@newsread1.news.pas.earthlink.net... > "Radio Active" wrote in message > news:1dsq81dg3pa3lngg121u8gaj2gij1m4eim@4ax.com... > > On Wed, 18 May 2005 03:45:42 GMT, "Marty Albert" > > was heard mumbling in the corner: > > > >>You are 100% correct... Lack of interest is, in my opinion, the largest > >>single factor. > >> > >>The speed is also a big deal, as you say... 1200 bps vs. a 2-4 Mbps cable > >>connection seems to be a slam dunk. > > > > The higher the speed the more the bandwidth needed to support it. We > > don't have the bandwidth in any of the spectrum we have to support 2-4 > > Mbps. > > What ??? You are joking, right? > > >>But, keep in mind that we are talking about is an easy to build and use > >>device that, with a 15+ year old design, was known to 80 Mbps over a > >>fairly > >>short path. > > > > How much bandwidth did it use? > > > >>That sort of makes mucking about with 802.11 junk sort of a wasted effort. > > > > ROFLOL! > > > >>The mistake was made about 15 years ago when the drive was to effectively > >>duplicate the Internet on the ham bands. Simply put, there are not, never > >>have been, and likely never will be enough hams in the world to do that. > >>Besides, why try to duplicate a defective system? > > > > The internet is defective? Interesting. So, your idea of what amateur > > radio should be is a national digital communications network? You have > > no room for other modes of communications? No SSB? No CW? > > > >>For the life of me, I can see no reason why Frank's device could not be > >>re-designed today to well over 512 Mbps, perhaps very close to gigabit > >>speeds. If you make the jump to the new copper solutions for 10 Gbps, we > >>may > >>even be able to get close to that... > > > > Look at the bandwidth 1200 bps or 9600 bps uses and then figure out > > what 512 Mbps would take up. Then read Part 97. > > What's the problem? > > >>Imagine a large metropolitan area, like maybe Dallas/Fort Worth, ringed by > >>an 8 Gbps nodes with spokes at 8 Gbps "dropping" into and through the > >>city. > >>A series of 1 Gbps nodes come off of the spokes to feed into the > >>neighborhood. In the neighborhoods, picture a bridge node that users can > >>connect to at, say, 100 Mbps. Lastly, picture these "City Wheels" being > >>connected to other city wheels at 10 Gbps. > > > > And just where are you going to get that much radio spectrum to do > > that? > > SHF. We already have the spectrum. > > >>Are you drooling yet? :) > > > > No, I'm laughing. > > Clueless but happy. > > -- > > ... Hank > > http://home.earthlink.net/~horedson > http://home.earthlink.net/~w0rli > > Article: 52384 of rec.radio.amateur.digital.misc From: "Charles Brabham" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1116443262.845591.277680@g49g2000cwa.googlegroups.com> <1116606190.674986.32450@g14g2000cwa.googlegroups.com> Subject: Re: Amazing Message-ID: <24vje.2514$VB6.2156@newssvr12.news.prodigy.com> Date: Sat, 21 May 2005 00:14:54 GMT "n3soz" wrote in message news:1116606190.674986.32450@g14g2000cwa.googlegroups.com... >I agree that this is vital to any large-scale regional network - don't > shut out the current packet infrastructure. I know there are TCP/IP > nodes that also support AX.25 connections so this should be possible. > > As to why this hasn't been done on a large scale - it would require > quite a bit of cooperation. A star topology would require several > sites with line-of-sight. Imagine a situation where four ham clubs > happen to have repeater sites that had line-of-sight, and your task was > to "sell" the backbone network concept to every club, and arrange the > logisitics of getting it all built. Besides raising funds there would > be issues of ownership and administration. > The Star network topology has been tried with Packet. It was called TexNet. The TexNet network did something that no other large-scale ax25 packet network ever did - It disappeared completely, leaving hardly any trace behind to show that it once existed.. From 100+ linked nodes to none in just a few years. I suppose that would qualify TexNet as the worst disaster in the history of digital amateur radio. It's untimely demise was directly related to the use of the obsolete Star network topology. All the other large-scale packet networks used the same Partially-Meshed network topology that the Internet utilizes, and I notice that all of those are still around to this day. Charles Brabham, N5PVL Director: USPacket http://www.uspacket.org Admin: HamBlog.Com http://www.hamblog.com Webmaster: HamPoll.Com http://www.hampoll.com Weblog: http://www.hamblog.com/blog_n5pvl.php Article: 52385 of rec.radio.amateur.digital.misc From: "Charles Brabham" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1116443262.845591.277680@g49g2000cwa.googlegroups.com> Subject: Re: Amazing Message-ID: <%dvje.2515$VB6.532@newssvr12.news.prodigy.com> Date: Sat, 21 May 2005 00:25:31 GMT "Hank Oredson" wrote in message news:jvmje.153$oT1.117@newsread1.news.pas.earthlink.net... > > We have done some test links, to verify path issues. > Then we did the cost analysis. > About $2k per endpoint for the paths we need to cover. > So we have some short links, but any interesting links require > investment from a group of hams instead of a single ham. > That has not happened. > > The problem is cost. By interesting, I assume you are talking about links that can be located a reasonable distance apart. I've been curious about this for quite a while. I use ethernet cable at home so I have no experience with WIFI equipment. Charles Brabham, N5PVL Director: USPacket http://www.uspacket.org Admin: HamBlog.Com http://www.hamblog.com Webmaster: HamPoll.Com http://www.hampoll.com Weblog: http://www.hamblog.com/blog_n5pvl.php Article: 52386 of rec.radio.amateur.digital.misc From: Paul Rubin Subject: Re: Amazing References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <1116443262.845591.277680@g49g2000cwa.googlegroups.com> <%dvje.2515$VB6.532@newssvr12.news.prodigy.com> Date: 20 May 2005 22:23:37 -0700 Message-ID: <7xzmupywx2.fsf@ruckus.brouhaha.com> "Hank Oredson" writes: > Five to fifty miles. > All costs included, things like towers, etc. as well as the dishes and > amplifiers. What are you using for the underlying RF? Ordinary wifi cards? How did you get them to operate outside the part 15 band? Article: 52387 of rec.radio.amateur.digital.misc From: Bob Nielsen Subject: Re: AGWPE for Linux? References: <1116644430.032721.25600@g49g2000cwa.googlegroups.com> Message-ID: Date: 21 May 2005 14:56:31 GMT On 20 May 2005 20:00:30 -0700, bc wrote: > Is there a program like agwpe that will run on Linux? > No, it isn't necessary since the Linux kernel supports AX.25. See for applications. -- Bob Nielsen, N7XY n7xy (at) n7xy.net Bainbridge Island, WA http://www.n7xy.net Article: 52388 of rec.radio.amateur.digital.misc From: "Marty Albert" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <9cadnZ5Xf5xbdRffRVn-ow@comcast.com> <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> Subject: Re: Amazing Message-ID: Date: Sat, 21 May 2005 17:53:16 GMT I will see if the University that I am using to develop the model will allow that at this point... It is actually their intellectual property. I doubt, however that you will find any major errors in the algorithms.... There have been many professors, PhDs, and grad students looking at it to find those errors as well as engineers from Motorola, Maxim, and TI. Take Care & 73 -- >From The Desk Of Marty Albert, KC6UFM "Hank Oredson" wrote in message news:4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net... > > The model is wrong. > Post it and I'll be glad to explain why. > Article: 52389 of rec.radio.amateur.digital.misc From: "Hank Oredson" References: <1116361519.813909.326290@g47g2000cwa.googlegroups.com> <9cadnZ5Xf5xbdRffRVn-ow@comcast.com> <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> Subject: Re: Amazing Message-ID: Date: Sat, 21 May 2005 19:16:55 GMT "The mathematical models show that 100 Mbps should be possible in as little as 10 KHz." If that is what it shows, there is an error. The error is either with the model itself, or with the assumptions fed into the model. Basic Thermo 101 ... Shannon ... etc. However, if you can get me 100 Mbps in 10 KHz, I'll be glad to buy a whole bunch of 'em :-) -- ... Hank http://home.earthlink.net/~horedson http://home.earthlink.net/~w0rli "Marty Albert" wrote in message news:gAKje.19443$J12.4755@newssvr14.news.prodigy.com... >I will see if the University that I am using to develop the model will >allow > that at this point... It is actually their intellectual property. > > I doubt, however that you will find any major errors in the algorithms.... > There have been many professors, PhDs, and grad students looking at it to > find those errors as well as engineers from Motorola, Maxim, and TI. > > Take Care & 73 > -- > From The Desk Of > Marty Albert, KC6UFM > > > "Hank Oredson" wrote in message > news:4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net... >> >> The model is wrong. >> Post it and I'll be glad to explain why. >> > > Article: 52390 of rec.radio.amateur.digital.misc From: "Caveat Lector" Subject: Question on web spiders Message-ID: Date: Sat, 21 May 2005 17:40:58 -0700 Maybe not the right place but seems there are several web experts here. Can web spiders read and harvest e-mail addresses from a pdf file ? Many users and folks like QRZ.com are using jpegs not ascii for listing e-mails -- this seems to work. So for pdf files without going to a jpeg --- are ascii text addresses harvestable ? Thanks -- CL -- I doubt, therefore I might be ! Article: 52391 of rec.radio.amateur.digital.misc From: mikea@mikea.ath.cx (Mike Andrews) Subject: Re: Question on web spiders Date: Sun, 22 May 2005 02:35:07 +0000 (UTC) Message-ID: References: Caveat Lector wrote: > Maybe not the right place but seems there are several web experts here. > Can web spiders read and harvest e-mail addresses from a pdf file ? > Many users and folks like QRZ.com are using jpegs not ascii for listing > e-mails -- this seems to work. > So for pdf files without going to a jpeg --- are ascii text addresses > harvestable ? Yes, in the sense that Optical Character Recognition (OCR) programs _can_ read text out of an image. In practice, it's not worth the spammers' or web spider operators' trouble -- or that's been my experience, anyway. YMMV. -- Mike Andrews, W5EGO mikea@mikea.ath.cx Tired old sysadmin Article: 52392 of rec.radio.amateur.digital.misc From: Paul Rubin Subject: Re: Question on web spiders References: Date: 21 May 2005 19:43:26 -0700 Message-ID: <7xu0kwou9d.fsf@ruckus.brouhaha.com> mikea@mikea.ath.cx (Mike Andrews) writes: > > So for pdf files without going to a jpeg --- are ascii text addresses > > harvestable ? > > Yes, in the sense that Optical Character Recognition (OCR) programs _can_ > read text out of an image. In practice, it's not worth the spammers' or > web spider operators' trouble -- or that's been my experience, anyway. PDF files contain the underlying text strings and search engines index them without OCR'ing. Whether spammers bother, I don't know. Article: 52396 of rec.radio.amateur.digital.misc From: nospam@w6yx.stanford.edu (Alan) Subject: Re: Amazing Date: Mon, 23 May 2005 08:16:10 +0000 (UTC) Message-ID: References: <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> In article "Marty Albert" writes: >I will see if the University that I am using to develop the model will allow >that at this point... It is actually their intellectual property. > >I doubt, however that you will find any major errors in the algorithms.... >There have been many professors, PhDs, and grad students looking at it to >find those errors as well as engineers from Motorola, Maxim, and TI. > >Take Care & 73 >-- >From The Desk Of >Marty Albert, KC6UFM > > >"Hank Oredson" wrote in message >news:4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net... >> >> The model is wrong. >> Post it and I'll be glad to explain why. A few things come to mind: 1) Multiplexing does not increase the bandwidth capability of a channel. You mention various forms of multiplexing, but these will not increase the channel capacity. They are just different ways of utilizing what is available. 2) The Hartley-Shannon Law gives the maximum bandwidth of a channel as C = B log2(1+(s/n)) bits/second; where B is bandwidth (Hz) and s/n is expressed as a value, not in dB. Given this, to get 80 megabits of signal in a 100 kilobit channel, you will need a signal/noise ratio of about 2408 dB. Since you were only starting with a 10 watt signal, with about 100 dB path loss (after including the two j-poles), and a terrrestrial noise floor of about -124 dBm for the 100 kHz wide channel, you get only about 60 - 64 dB s/n in your receiver (assuming things like lossless coax, etc.). Thus you are about 2340 dB short on signal to accomplish the task as described. See http://encyclopedia.laborlawtalk.com/Shannon_limit for more discussion of this. Your numbers are a bit too far from what can reasonably be believed. Alan wa6azp Article: 52397 of rec.radio.amateur.digital.misc From: "Hank Oredson" References: <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> Subject: Re: Amazing Message-ID: Date: Mon, 23 May 2005 15:58:12 GMT "Alan" wrote in message news:d6s3ga$ph5$1@news.Stanford.EDU... > In article "Marty > Albert" writes: >>I will see if the University that I am using to develop the model will >>allow >>that at this point... It is actually their intellectual property. >> >>I doubt, however that you will find any major errors in the algorithms.... >>There have been many professors, PhDs, and grad students looking at it to >>find those errors as well as engineers from Motorola, Maxim, and TI. >> >>Take Care & 73 >>-- >>From The Desk Of >>Marty Albert, KC6UFM >> >> >>"Hank Oredson" wrote in message >>news:4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net... >>> >>> The model is wrong. >>> Post it and I'll be glad to explain why. > > > A few things come to mind: > > 1) Multiplexing does not increase the bandwidth capability of a > channel. > You mention various forms of multiplexing, but these will not increase > the channel capacity. They are just different ways of utilizing what > is available. > > 2) The Hartley-Shannon Law gives the maximum bandwidth of a channel as > C = B log2(1+(s/n)) bits/second; where B is bandwidth (Hz) and s/n is > expressed as a value, not in dB. > > Given this, to get 80 megabits of signal in a 100 kilobit channel, you > will need a signal/noise ratio of about 2408 dB. Since you were only > starting with a 10 watt signal, with about 100 dB path loss (after > including > the two j-poles), and a terrrestrial noise floor of about -124 dBm for the > 100 kHz wide channel, you get only about 60 - 64 dB s/n in your receiver > (assuming things like lossless coax, etc.). > Thus you are about 2340 dB short on signal to accomplish the task as > described. See http://encyclopedia.laborlawtalk.com/Shannon_limit for > more > discussion of this. > > > Your numbers are a bit too far from what can reasonably be believed. Thanks for doing the math :-) I thought he claimed a 10 KHz channel ... but might be wrong. You could cool the receiver and heat the transmitter (1500W, larger dish) and get perhaps 20 - 40 more db ... that would help :-) Then you might be only 2300 db short. -- ... Hank http://home.earthlink.net/~horedson http://home.earthlink.net/~w0rli Article: 52398 of rec.radio.amateur.digital.misc From: "Marty Albert" References: <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> Subject: Re: Amazing Message-ID: Date: Tue, 24 May 2005 01:44:15 GMT I was wondering when someone would stumble across the Hartley-Shannon "law"... Like most laws of this nature, they break down at the extremes (i.e. Relativity fails on the scale of the very small and Quantum Mechanics fails on the scale of the very large... For my money, I'm betting on M Theory (formerly String Theory) to be the true GUT). Plug the numbers in for CAT6 over 100 m running a 10 Gbps data stream. You will find that the equation fails in that it will tell that you can't do that and, if set up right, it will send you the fact that it is impossible OVER the 10 Gbps, 100 m run. By the same token, if you plug in numbers for, say, 1.2 Kbps over CAT6 of 500 m length, that won't work either. The fact is, we (the telecomm/data comm industry) do it every day. Keep in mind that we all tend to "think inside the box" and say that things (pick one) are impossible because of some theory or "law". As a general rule, we end up being wrong. Case in point, everyone knows that the velocity of light (c) is the "Cosmic Speed Limit". Einstein said so and had the math to prove it. Quantum Mechanics and M Theory both have solutions that allow for FTL... And some have some rather unpleasant side effects. But enough of the arcane math and other arenas... Try to "think outside of the box"... Think about ways to do: 1) Ultra high speed data over RF media; 2) Make the system so cheap and easy that everyone will want one; 3) Perhaps get the attention of the commercial sector. Everyone sitting around bemoaning the obstacles that need to be over come are counter productive. There is no such thing as "I can't do that." There is only "I won't do that." At the risk of sounding Republican (which I am) and of sounding like I agree with President Bush (which I do not at least 50% of the time) you need to decide how much, if any, effort, thinking, and support you are willing to give. If you are interested in digital modes, you will be willing to put in what is needed. If you are not interested in the digital modes, you should at least get out of the way of those who do. But, I wax philosophical... And even with 2 doctorate degrees, neither qualifies me to be a philosopher. Take Care & 73 -- >From The Desk Of Marty Albert, KC6UFM "Alan" wrote in message news:d6s3ga$ph5$1@news.Stanford.EDU... > In article "Marty Albert" writes: > >I will see if the University that I am using to develop the model will allow > >that at this point... It is actually their intellectual property. > > > >I doubt, however that you will find any major errors in the algorithms.... > >There have been many professors, PhDs, and grad students looking at it to > >find those errors as well as engineers from Motorola, Maxim, and TI. > > > >Take Care & 73 > >-- > >From The Desk Of > >Marty Albert, KC6UFM > > > > > >"Hank Oredson" wrote in message > >news:4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net... > >> > >> The model is wrong. > >> Post it and I'll be glad to explain why. > > > A few things come to mind: > > 1) Multiplexing does not increase the bandwidth capability of a channel. > You mention various forms of multiplexing, but these will not increase > the channel capacity. They are just different ways of utilizing what > is available. > > 2) The Hartley-Shannon Law gives the maximum bandwidth of a channel as > C = B log2(1+(s/n)) bits/second; where B is bandwidth (Hz) and s/n is > expressed as a value, not in dB. > > Given this, to get 80 megabits of signal in a 100 kilobit channel, you > will need a signal/noise ratio of about 2408 dB. Since you were only > starting with a 10 watt signal, with about 100 dB path loss (after including > the two j-poles), and a terrrestrial noise floor of about -124 dBm for the > 100 kHz wide channel, you get only about 60 - 64 dB s/n in your receiver > (assuming things like lossless coax, etc.). > Thus you are about 2340 dB short on signal to accomplish the task as > described. See http://encyclopedia.laborlawtalk.com/Shannon_limit for more > discussion of this. > > > Your numbers are a bit too far from what can reasonably be believed. > > > Alan > wa6azp Article: 52399 of rec.radio.amateur.digital.misc From: Paul Rubin Subject: Re: Amazing References: <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> Date: 23 May 2005 18:47:00 -0700 Message-ID: <7xsm0dtmy3.fsf@ruckus.brouhaha.com> "Marty Albert" writes: > Case in point, everyone knows that the velocity of light (c) is the "Cosmic > Speed Limit". Einstein said so and had the math to prove it. Quantum > Mechanics and M Theory both have solutions that allow for FTL... And some > have some rather unpleasant side effects. Some wise old philosopher might have said, if someone tries to sell you an FTL car, don't bet the farm on it. Your 100 MBPS in 100 khz scheme works out about the same way. Article: 52400 of rec.radio.amateur.digital.misc From: "Hank Oredson" References: <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> Subject: Re: Amazing Message-ID: Date: Tue, 24 May 2005 03:51:34 GMT "Marty Albert" wrote in message news:PFvke.20533$J12.5026@newssvr14.news.prodigy.com... >I was wondering when someone would stumble across the Hartley-Shannon > "law"... What do you mean "stumble across it" ??? > Like most laws of this nature, they break down at the extremes (i.e. > Relativity fails on the scale of the very small and Quantum Mechanics > fails > on the scale of the very large... For my money, I'm betting on M Theory > (formerly String Theory) to be the true GUT). Shannon's theorem, Hartley-Shannon, etc. just describe what nature does. > Plug the numbers in for CAT6 over 100 m running a 10 Gbps data stream. You > will find that the equation fails in that it will tell that you can't do > that and, if set up right, it will send you the fact that it is impossible > OVER the 10 Gbps, 100 m run. Um ... no ... > By the same token, if you plug in numbers for, say, 1.2 Kbps over CAT6 of > 500 m length, that won't work either. The fact is, we (the telecomm/data > comm industry) do it every day. Um ... no ... > Keep in mind that we all tend to "think inside the box" and say that > things > (pick one) are impossible because of some theory or "law". As a general > rule, we end up being wrong. Um ... no ... > Case in point, everyone knows that the velocity of light (c) is the > "Cosmic > Speed Limit". Einstein said so and had the math to prove it. Quantum > Mechanics and M Theory both have solutions that allow for FTL... And some > have some rather unpleasant side effects. Um ... no ... > But enough of the arcane math and other arenas... > > Try to "think outside of the box"... Think about ways to do: > > 1) Ultra high speed data over RF media; What is hard about that? > 2) Make the system so cheap and easy that everyone will want one; If you think you have a way to do so, I will buy a *bunch* of them. Send me a quote via email. Will submit the order. > 3) Perhaps get the attention of the commercial sector. Odd, I kinda suspect the "commercial sector" is doing some work on this. > Everyone sitting around bemoaning the obstacles that need to be over come > are counter productive. Oh, good. Send me that quote. > There is no such thing as "I can't do that." Yes, there is. > There is only "I won't do that." It is nature that will "not do that". > At the risk of sounding Republican (which I am) and of sounding like I > agree > with President Bush (which I do not at least 50% of the time) you need to > decide how much, if any, effort, thinking, and support you are willing to > give. You need to take Thermo 101. > If you are interested in digital modes, you will be willing to put in what > is needed. What is needed? > If you are not interested in the digital modes, you should at least get > out > of the way of those who do. Send me that quote. > But, I wax philosophical... And even with 2 doctorate degrees, neither > qualifies me to be a philosopher. That is quite clear. > Take Care & 73 > -- > From The Desk Of > Marty Albert, KC6UFM > > > "Alan" wrote in message > news:d6s3ga$ph5$1@news.Stanford.EDU... >> In article "Marty > Albert" writes: >> >I will see if the University that I am using to develop the model will > allow >> >that at this point... It is actually their intellectual property. >> > >> >I doubt, however that you will find any major errors in the > algorithms.... >> >There have been many professors, PhDs, and grad students looking at it >> >to >> >find those errors as well as engineers from Motorola, Maxim, and TI. >> > >> >Take Care & 73 >> >-- >> >From The Desk Of >> >Marty Albert, KC6UFM >> > >> > >> >"Hank Oredson" wrote in message >> >news:4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net... >> >> >> >> The model is wrong. >> >> Post it and I'll be glad to explain why. >> >> >> A few things come to mind: >> >> 1) Multiplexing does not increase the bandwidth capability of a > channel. >> You mention various forms of multiplexing, but these will not increase >> the channel capacity. They are just different ways of utilizing what >> is available. >> >> 2) The Hartley-Shannon Law gives the maximum bandwidth of a channel >> as >> C = B log2(1+(s/n)) bits/second; where B is bandwidth (Hz) and s/n is >> expressed as a value, not in dB. >> >> Given this, to get 80 megabits of signal in a 100 kilobit channel, you >> will need a signal/noise ratio of about 2408 dB. Since you were only >> starting with a 10 watt signal, with about 100 dB path loss (after > including >> the two j-poles), and a terrrestrial noise floor of about -124 dBm for >> the >> 100 kHz wide channel, you get only about 60 - 64 dB s/n in your receiver >> (assuming things like lossless coax, etc.). >> Thus you are about 2340 dB short on signal to accomplish the task as >> described. See http://encyclopedia.laborlawtalk.com/Shannon_limit for > more >> discussion of this. >> >> >> Your numbers are a bit too far from what can reasonably be believed. >> >> >> Alan >> wa6azp > > Article: 52401 of rec.radio.amateur.digital.misc From: "Hank Oredson" References: <4wzje.4358$Lc1.3532@newsread3.news.pas.earthlink.net> <7xsm0dtmy3.fsf@ruckus.brouhaha.com> Subject: Re: Amazing Message-ID: Date: Tue, 24 May 2005 03:54:59 GMT "Paul Rubin" wrote in message news:7xsm0dtmy3.fsf@ruckus.brouhaha.com... > "Marty Albert" writes: >> Case in point, everyone knows that the velocity of light (c) is the >> "Cosmic >> Speed Limit". Einstein said so and had the math to prove it. Quantum >> Mechanics and M Theory both have solutions that allow for FTL... And some >> have some rather unpleasant side effects. > > Some wise old philosopher might have said, if someone tries to sell > you an FTL car, don't bet the farm on it. > > Your 100 MBPS in 100 khz scheme works out about the same way. It is the exact equivalent of those little pills you drop into the gas tank of your car, and then get 100 MPG from water. However, there is one difference. I can purchase those pills, test them, and destroy my engine while getting 10 MPG :-) I cannot purchase the magic "Shannon violating channel". As a side note, strings are not yet a GUT, other than on fiddles. -- ... Hank http://home.earthlink.net/~horedson http://home.earthlink.net/~w0rli Article: 52403 of rec.radio.amateur.digital.misc From: "gareth" Subject: Re: TWO DAYS TO GO (to teh most important day in Ham radio History) Date: 25 May 2005 01:29:00 GMT Message-ID: References: <1116961504.581733.211120@o13g2000cwo.googlegroups.com> First of all: Sorry about the cross post but IMHO this has worldwide reprocushions: The CONSULTATION will be open on 26th of May: On 26th of May "OfCom" the UK's Radio Authority will issue a consulation document on the future of Amateur Radio Licensing in the UK. The consulation is open to all and will ask a number of questions on options such as licence for life, de-regulation and: "..options to make the (UK) amateur radio service WT Act licence-exempt" Just so you do not miss this important event in world amateur radio, add yourself to the mailing list here: http://www.ofcom.org.uk/static­/subscribe/radiospectrum.htm ....and HAVE YOUR SAY !!! You will be emailed on May 26th, immediately the consulation is published. HAVE YOUR SAY !!! HAVE YOUR SAY !!! HAVE YOUR SAY !!! HAVE YOUR SAY !!! HAVE YOUR SAY !!! HAVE YOUR SAY !!! (Follow ups will just go to: uk.radio.amateur - sorry- netcops!) --73deG1LVN in the meantime: Sohttp://qsy.to/ChorleyFM