|
BPL *IS* Going to Happen- Get Ready
David,
Looks like I'm going to have to research some nice linear as well as a decent HF station. I had been looking at a vertical to avoid all of the horizontal lines in the neighborhood, but, on second thought ... 1500 watts horizontally polarized, 50 feet from the power lines might prove interesting :) 73 from Rochester, NY Jim AA2QA ps - we need a study as to where the biggest ingress will occur :) "David Stinson" wrote in message ... Money talks, public service walks- BPL is a certainty. The "null it out- anyone can do it" argument is crap- works well in theory, poorly in the field. Even with excellent nulling, QRP and other weak signal work is finished. Shortwave DXing is finished. You have three choices- Give up radio. Move far enough into the country to avoid the polluted grid, "Gorilla warfare-" Power lines that leak out, can also leak IN. 50 watts of broadband noise generator plugged into the nearest socket would do. Note that I would never advocate anything illegal..... D.S. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.512 / Virus Database: 309 - Release Date: 8/19/03 |
Amazing, a scenario where an SWL would move into the city because of
less QRN. On Sun, 24 Aug 2003 15:41:04 GMT, David Stinson wrote: Money talks, public service walks- BPL is a certainty. The "null it out- anyone can do it" argument is crap- works well in theory, poorly in the field. Even with excellent nulling, QRP and other weak signal work is finished. Shortwave DXing is finished. You have three choices- Give up radio. Move far enough into the country to avoid the polluted grid, "Gorilla warfare-" Power lines that leak out, can also leak IN. 50 watts of broadband noise generator plugged into the nearest socket would do. Note that I would never advocate anything illegal..... D.S. |
"Jim Hampton" wrote in message ... David, Looks like I'm going to have to research some nice linear as well as a decent HF station. I had been looking at a vertical to avoid all of the horizontal lines in the neighborhood, but, on second thought ... 1500 watts horizontally polarized, 50 feet from the power lines might prove interesting :) 73 from Rochester, NY Jim AA2QA ps - we need a study as to where the biggest ingress will occur :) Hmmm. I can't imagine any way Ham radio interference would do any good, even if legal. Interference might not have effect it at all. Or it might cause a slowdown the BPL user would attribute to internet congestion. If the BPL user believes interference is casuing a problem with his gee-whiz powerline internet access, he's gonna squak to the power company and maybe the FCC. Face it, radio hobbyists are in no position for poor public relations. There are more people who will be attracted to the bright, shiny promise of BPL than there are radio hobbyists. Considering the numbers, would it be unlikely for the FCC to redefine the interference limits? I'd be curious to know how vunerable BPL is to interference. I have no doubt the BPL people have run tests, and I'm a little surprised they're not at the front of a webpage somewhere. Ham radio may not have alot of effect. The power lines will only absorb a fraction of what's transmitted, and will probably re-radiate most of that. I would think interference from devices plugged directly into the lines would have the most effect. Like spikey old universal motors and cheap switchmode power supplies. Politically, it's far better if damaging interference comes from everyday objects around the home. Like the vacuum cleaner, the microwave oven, the kid's computer, etc. And nothing will help as much as bringing new people into the radio hobby. Frank Dresser |
I use the power line as an antenna for my baby SW RXs, when I carry them around
the house. In fact, using the power line provides better recpetion at 3.21 MHz on my Grundig eTR7 than I get with my 40M inverted vee on my DX-392. LOL Using the baby RXs on the power line, BPL might be fun. Bill, K5BY |
"Brian Kelly" wrote in message om... I'd be curious to know how vunerable BPL is to interference. I have no doubt the BPL people have run tests, and I'm a little surprised they're not at the front of a webpage somewhere. No sir, the BPL clods have *not* done much if any interfernce testing wherein lies the underlying reason for whole uproar and is the reason you can't find info on their "tests" online. It's all explained in depth and well documented in the ARRL website. When I wrote "vunerable BPL is to interference", I meant how outside sources of interference would effect the performance of BPL. Sorry if I wasn't clear. I still have no doubt the BPL people would test for things like that. I wouldn't expect them to care much about interference, as long as they can fit it into some interpretation of Part 15 regs. Or if they can get the Part 15 regs changed. Or if they don't get caught violating the Part 15 regs. I was wondering if there's any test results explaining how marvelously robust this BPL system is going to be. If you know where this is all explained in depth and well documented, please point me in that direction. And nothing will help as much as bringing new people into the radio hobby. By the time that might happen BPL will either have taken over the HF spectrum or been forgotten as another idiotic and failed dotcom maneuver. BPL might very well fail. Or it might hang on in a few communities. I have no idea. I'm sure, now that crackpot powerline schemes are here, they will never really go away. Far beyond the question of hams interfering with BPL comes the much more important question of BPL interfering with the long list of licensed incumbent HF users. Within that group radio hobbyists are basically bit players. Smart and noisy bit players but nonetheless bit players. Other users are *not* bit players and them's the folks who I expect will quietly and decisively torpedo BPL. w3rv Maybe, but much of the utility SW use has gone to sattelites. The bands are far quiter now than they were 30 years ago. Of course, I've got my own crackpot idea. The SW spectrum should be run rather like the way we run the National Parks. Everyone is free to use SW radio, as long as they act in a responsible manner. If only Boy Scouts could go to Yellowstone, only Boy Scouts would care about Yellowstone. Frank Dresser |
Jim:
Even BEFORE they start this BPL thing, the existing power lines emanate a ton of interference anyways. It is almost impossible for me to listen to anything HF around here because the lines around here are terrible. I can only imagine how much worse it will get with adding the BPL stuff as well. I am definitely a proponent of having the utilities switching (albeit expensive) to buried electrical lines. Only exception might be where the lines need to cross a river etc. -- Ryan, KC8PMX FF1-FF2-MFR-(pending NREMT-B!) --. --- -.. ... .- -. --. . .-.. ... .- .-. . ..-. .. .-. . ..-. ... --. .... - . .-. ... "Jim Hampton" wrote in message ... David, Looks like I'm going to have to research some nice linear as well as a decent HF station. I had been looking at a vertical to avoid all of the horizontal lines in the neighborhood, but, on second thought ... 1500 watts horizontally polarized, 50 feet from the power lines might prove interesting :) 73 from Rochester, NY Jim AA2QA ps - we need a study as to where the biggest ingress will occur :) "David Stinson" wrote in message ... Money talks, public service walks- BPL is a certainty. The "null it out- anyone can do it" argument is crap- works well in theory, poorly in the field. Even with excellent nulling, QRP and other weak signal work is finished. Shortwave DXing is finished. You have three choices- Give up radio. Move far enough into the country to avoid the polluted grid, "Gorilla warfare-" Power lines that leak out, can also leak IN. 50 watts of broadband noise generator plugged into the nearest socket would do. Note that I would never advocate anything illegal..... D.S. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.512 / Virus Database: 309 - Release Date: 8/19/03 |
"Frank Dresser" wrote in message ...
"Brian Kelly" wrote in message om... I'd be curious to know how vunerable BPL is to interference. I have no doubt the BPL people have run tests, and I'm a little surprised they're not at the front of a webpage somewhere. No sir, the BPL clods have *not* done much if any interfernce testing wherein lies the underlying reason for whole uproar and is the reason you can't find info on their "tests" online. It's all explained in depth and well documented in the ARRL website. When I wrote "vunerable BPL is to interference", I meant how outside sources of interference would effect the performance of BPL. Sorry if I wasn't clear. No problem, I understood what you meant. I still have no doubt the BPL people would test for things like that. I wouldn't expect them to care much about interference, as long as they can fit it into some interpretation of Part 15 regs. Or if they can get the Part 15 regs changed. Or if they don't get caught violating the Part 15 regs. I was wondering if there's any test results explaining how marvelously robust this BPL system is going to be. If you know where this is all explained in depth and well documented, please point me in that direction. From http://www.arrl.org/news/stories/2003/08/21/4/?nc=1 "The League also noted that comments in the proceeding so far have been silent on the interference susceptibility of BPL to ham radio signal ingress. The League predicted that even as little as 250 mW of signal induced into overhead power lines some 100 feet from an amateur antenna could degrade a BPL system or render it inoperative." I realize that this is not the statement about actual tests run by the BPL people which you'd like to see, they haven't published *any* test results at all, but the League technical guys are pretty sharp and I doubt they'd make a statement like this if that didn't have a good basis for making it. And nothing will help as much as bringing new people into the radio hobby. By the time that might happen BPL will either have taken over the HF spectrum or been forgotten as another idiotic and failed dotcom maneuver. BPL might very well fail. Or it might hang on in a few communities. I have no idea. I'm sure, now that crackpot powerline schemes are here, they will never really go away. Heh. Yeah, the recent grid debacle is not setting a very good stage for a huggy kissy relationship between the BPL types and *anybody* else including the FCC. I've seen some economic analyses of BPL and from the standpoint of an investor BPL is a big go-nowhere dud. Far beyond the question of hams interfering with BPL comes the much more important question of BPL interfering with the long list of licensed incumbent HF users. Within that group radio hobbyists are basically bit players. Smart and noisy bit players but nonetheless bit players. Other users are *not* bit players and them's the folks who I expect will quietly and decisively torpedo BPL. w3rv Maybe, but much of the utility SW use has gone to sattelites. The bands are far quiter now than they were 30 years ago. That's quite true. But we can't hear HF listeners and we can't normally tune some modes but they're out there and apparently in profusion. We almost didn't get any 60M band at all because certain feds didn't want hams on "their HF frequencies". I dunno who they are, those freqs appear dead when ya tune around. But they're there. FBI, CIA, NSA, FCC, the military? Of course, I've got my own crackpot idea. The SW spectrum should be run rather like the way we run the National Parks. From a post I launched in RRAP on 8 Feb 2000: - - - - - W3RV "There isn't enough bandwidth in all the HF ham bands combined to pull off the kinds of ham technology development work we'll see in the coming years, much of it undoubtedly will be done by nocode computer jocks on the millimeter bands. Code tests have been a no-counter wrt to "fostering ham radio as a tehnical hobby" for the past nine years". K4YZ: and that HF is for recreation, period. W3RV: "PRECISELY: If I had my druthers I'd have the regulation of HF ham radio moved over to the National Park Service and let the geeks screw around with the FCC." - - - - - Heh! Everyone is free to use SW radio, as long as they act in a responsible manner. NO WAY!! If only Boy Scouts could go to Yellowstone, only Boy Scouts would care about Yellowstone. Frank Dresser w3rv |
In rec.radio.amateur.policy Frank Dresser wrote:
When I wrote "vunerable BPL is to interference", I meant how outside sources of interference would effect the performance of BPL. Sorry if I wasn't [..] If you know where this is all explained in depth and well documented, please point me in that direction. I don`t know the details, but here in Europe several pilot projects were basically stopped and several larger companies got out of that technology again, after trying to hype it for several years. I do not know if this is due to unreliability or due to other factors, but it *seems* to have worked better in the lab than in the real world. If enough problems make it too unreliable and/or expensive, this might be the easiest way out. There *are* some companies still trying to bring this to market though (my local utility does). /ralph |
"Ralph Aichinger" wrote in message ... I don`t know the details, but here in Europe several pilot projects were basically stopped and several larger companies got out of that technology again, after trying to hype it for several years. I do not know if this is due to unreliability or due to other factors, but it *seems* to have worked better in the lab than in the real world. If enough problems make it too unreliable and/or expensive, this might be the easiest way out. There *are* some companies still trying to bring this to market though (my local utility does). /ralph Yeah. As proposed, it might have too many problems to go into widespread use. However, if the biggest problem is their signal to noise ratio, they might fix it by boosting their signal. Let's hope not! Frank Dresser |
"Frank Dresser" analogdial@worldnet
If radio were open to the public, there would be thousands more people who give a damn about radio. And any politican will desire the support of thousands who give a damn every bit as much as he desires a snappy wardrobe and a full head of hair. Hey Frank, where'd you ever get the idea that radio *isn't* open to the public? I never knew anyone whatever who wanted a ham radio license who was barred from getting one. There is a small matter of qualifying for it, of course, as there is in every endeavor where others can and will be impacted when the licensee knows not which way is up. But it has always been open to all comers. Now if you're talking "open" like CB is open, that's a horse of an entirely different color. Dick |
"CW" wrote in message news:zEP2b.267374$o%2.121884@sccrnsc02... I think there is a big panic about something that will probably be a minor annoyance to some. Not a problem to most. Do people seriously think that airports are just going to cease communicating with their planes? How about the military HF network. I can see them now. Sitting around the pentagon saying "forget national security, people have to get their email". Think about it. It's my wild ass guess that BPL won't be a big success, but I do think cheating on the BPL power will be a real temptation. Anyway, it will be tough on radio hobbyists in a BPL neighborhood, and it certainly will be heard over a wider region. But, you're probably right. The world isn't coming to an end over this. Brother Stair has been quiet on the whole BPL issue. Frank Dresser |
"DickCarroll" wrote in message om... "Frank Dresser" analogdial@worldnet Hey Frank, where'd you ever get the idea that radio *isn't* open to the public? I never knew anyone whatever who wanted a ham radio license who was barred from getting one. There is a small matter of qualifying for it, of course, as there is in every endeavor where others can and will be impacted when the licensee knows not which way is up. But it has always been open to all comers. OK, amateur radio is open to the public. But nearly all amateur radio activity is either contacts between hams or some sort of test. I'm under the impression that amatuers broadcasting what might be considered entertainment programming to the public is banned. Am I wrong about that? Now if you're talking "open" like CB is open, that's a horse of an entirely different color. Dick More like pirate radio. I've heard some very entertaining stuff, and I hope to hear alot more. I know that time can be bought on an independent broadcaster, but I'd really like to know why what Alan Maxwell and the other do is illegal. I think hobby broadcasting would bring alot of positive interest to SW radio. Frank Dresser |
"Frank Dresser" wrote in message ... More like pirate radio. I've heard some very entertaining stuff, and I hope to hear alot more. I know that time can be bought on an independent broadcaster, but I'd really like to know why what Alan Maxwell and the other do is illegal. I think hobby broadcasting would bring alot of positive interest to SW radio. Frank Dresser It may be fun, but keep in mind a few things. 1) It is difficult to control where a signal goes. 2) There are international agreements that help to avoid interference. Given the above, allowing radio to be a free for all would only serve to promote interference from stations on the same frequency. That interference can detract from people listening to transmissions that are complying with the agreements and laws. Interference can have serious results if it interferes with aircraft or miliraty communications. Just imagine the shortwave spectrum being used just like the 27 MHz band. I'd rather have the order that the laws and agreements provide. craigm |
Frank Dresser wrote:
"DickCarroll" wrote in message om... "Frank Dresser" analogdial@worldnet Hey Frank, where'd you ever get the idea that radio *isn't* open to the public? I never knew anyone whatever who wanted a ham radio license who was barred from getting one. There is a small matter of qualifying for it, of course, as there is in every endeavor where others can and will be impacted when the licensee knows not which way is up. But it has always been open to all comers. OK, amateur radio is open to the public. But nearly all amateur radio activity is either contacts between hams or some sort of test. I'm under the impression that amatuers broadcasting what might be considered entertainment programming to the public is banned. Am I wrong about that? No, you're absolutely right. Amateur broadcasting is banned-only point to point comms between hams are allowed. In fact, what you could call amateur broadcasting is banned on ALL bands. Nobody wants to listen to the Liberty Net, or be limited by archaic rules made in the 1920s as to what types of comms hams are limited to. Now if you're talking "open" like CB is open, that's a horse of an entirely different color. Dick More like pirate radio. I've heard some very entertaining stuff, and I hope to hear alot more. I know that time can be bought on an independent broadcaster, but I'd really like to know why what Alan Maxwell and the other do is illegal. I think hobby broadcasting would bring alot of positive interest to SW radio. The FCC's standard excuse is that band space is a finite resource. True enough. But if there's enough room for point to point hams on SW, then a portion of band spectrum could easily be allocated for amateur broadcasting-like pirate radio except with licenses and allocated frequencies. Take an old utility band and use it for broadcasting. Licensing of amateur broadcasting would allow the Alan Maxwells of the US to do what they do while giving the FCC a stick to use against truly malicious operators, like the guys who used to interrupt police radios, or the pirates who choose international air freqs. And the best part would be that people wouldn't have to break the law and risk absurd fines (the highest in the world, from what I've heard) to be hobbyists. I fail to see how amateur broadcasting on SW endangers the audiences of mainstream AM and FM stations. One final note, many of radio's pioneers were amateur broadcasters. Like Charles Herrold of San Jose (CA) who was broadcasting phonograph music before there were any radio regulations at ALL. He would identify each broadcast by reading the address of his engineering college over the air. Or Fessenden or whatever his name was who broadcast music and voices to ship radio ops (at a time when Morse code was all that was allowed). Early on, amateur and ship licenses were the only ones available, so amateurs DID broadcast. Once Westinghouse showed there was a profitable market for general broadcasting, the hams were summarily booted off AM (550-1500 khz then) and moved up to "useless" shortwave. |
Frank Dresser wrote:
"Brian Kelly" wrote in message om... From http://www.arrl.org/news/stories/2003/08/21/4/?nc=1 "The League also noted that comments in the proceeding so far have been silent on the interference susceptibility of BPL to ham radio signal ingress. The League predicted that even as little as 250 mW of signal induced into overhead power lines some 100 feet from an amateur antenna could degrade a BPL system or render it inoperative." I realize that this is not the statement about actual tests run by the BPL people which you'd like to see, they haven't published *any* test results at all, but the League technical guys are pretty sharp and I doubt they'd make a statement like this if that didn't have a good basis for making it. Thanks. I do think interference is going to be a real problem for BPL performance, but ham radio interference will be a very small part of that. I suspect household devices will be far more significant. I have an air purifier that spews RF all over the tropical bands. I have to turn it off to get Peru or whatever. And then there's flourescent light ballasts. Think of BPL as flourescent lights times a zillion. |
"Gray Shockley" wrote in message ... Do you mean in place of CB, using CB freqs or ???? Thanks, That would be great.. it's not like the band is being used for it's intended purpose anyway. Besides, a good portion of the "traffic" on the 11m band is music and sound effects anyway.. LOL. Just think, maybe you could get some people on there actually TRYING to get decent sounding audio on their stations so that their music programming could be more listenable. I could do it in a heartbeat, but most CB types only know how to blast hundreds of filthy watts out and splatter 12 channels each way... |
In rec.radio.amateur.policy CW wrote:
I think there is a big panic about something that will probably be a minor annoyance to some. Not a problem to most. Do people seriously think that airports are just going to cease communicating with their planes? How about That is done on VHF, not on HF, AFAIK the military HF network. I can see them now. Sitting around the pentagon saying "forget national security, people have to get their email". Think about it. BPL chipsets can keep some frequency ranges free from QRM. Somebody in the german ham newsgroup has looked at it with a spectrum analyzer or whatever. And I think military users could change to VHF or UHF, even sat communications anyway if they wanted. They could also keep BPL out of special areas. I doubt military users in suburban environments give a damn about HF. BPL *is* a real threat. /ralph |
"Gray Shockley" wrote in message ... On Tue, 26 Aug 2003 23:17:45 -0500, Frank Dresser wrote (in message ): How's the 11 meter SW band for the hobby broadcasters? The international broadcasters have pretty much abandonded it, the antennas should be easy to work with and line of sight will work even when the ionosphere doesn't. Frank Dresser Do you mean in place of CB, using CB freqs or ???? Thanks, Gray Shockley 25.6 to 26.1 Mhz, just below the Citizen's Band. It's already set aside as a SW broadcast band, although the broadcasters rarely use it. Frank Dresser |
And if you decided o realocate the band, they would continue to use it
making it just as useless as it is today. In any case, it is not all crap. If you get out on the road, you will find that truckers are still using it for its intended purpose. "Brenda Ann" wrote in message ... "Gray Shockley" wrote in message ... Do you mean in place of CB, using CB freqs or ???? Thanks, That would be great.. it's not like the band is being used for it's intended purpose anyway. Besides, a good portion of the "traffic" on the 11m band is music and sound effects anyway.. LOL. Just think, maybe you could get some people on there actually TRYING to get decent sounding audio on their stations so that their music programming could be more listenable. I could do it in a heartbeat, but most CB types only know how to blast hundreds of filthy watts out and splatter 12 channels each way... |
"CW" wrote in message news:8543b.274761$YN5.187296@sccrnsc01... The freebanders use it all the time and they wouldn't stop. I haven't heard the freebanders there, but I was hearing about half a dozen of the 26 Mhz link transmitters, back about three years ago. I'm not disputing what you're saying, but I think the bulk of the freebanders transmit up a bit higher. Anyway, the reason the freebanders can transmit without any restrictions is not because there are no rules, but because they're aren't enough people who will go to the effort to enforce them. Freebanders don't bother me, so I guess I'm one of those who don't care, as well. But I'd like to see some people move into SW radio's abandonded property. Sure, they may have a different idea of fun than some of the current residents, but if they keep the place up, who'd care? Especially if they're entertaining sorts of people who have plenty of loyal friends incase a real threat turns up someday. And the squatters just might move out or go legit. Frank Dresser Frank Dresser |
Frank Dresser wrote:
"Gray Shockley" wrote in message ... On Tue, 26 Aug 2003 23:17:45 -0500, Frank Dresser wrote (in message ): How's the 11 meter SW band for the hobby broadcasters? The international broadcasters have pretty much abandonded it, the antennas should be easy to work with and line of sight will work even when the ionosphere doesn't. Frank Dresser Do you mean in place of CB, using CB freqs or ???? Thanks, Gray Shockley 25.6 to 26.1 Mhz, just below the Citizen's Band. It's already set aside as a SW broadcast band, although the broadcasters rarely use it. Problem: most portables don't go that high. My DX396, for example, only goes up to 21850 khz. Also, thewre's a lot of freebanders in that area, apparently. 13m (starting around 21450) is barely used by major stations, and would have similar propagation to 11m. |
In rec.radio.amateur.policy CW wrote:
There are active military and government frequencies spread throughout the HF bands, I have, sitting in front of me, two pages worth of active military frequencies. This does not include FEMA, DEA, ect. Yes, they also use VHF and satellite but maintain activity on HF for long distance as VHF is line of sight and satellites are to vulnerable. You can do everything you want to maintain your chicken little views but some of us know better. As I have written, BPL devices *do* have the possibility to keep out of *some* HF frequencies AFAIK. Ham radio would not be the first candidate for this. Air mobile and military users would be more likely to benefit from it. And maybe it is a different perspective here in Austria, as our military has a lot less influence on our society. We've got utilities actively deploying this stuff, and while it is far from being everywhere, it is a real threat in some areas. I suppose they could not care less about implications of BPL for the military. They just do good lobbying, and they have shown their political influence in many issues in the past. Don't count too much on the military. They might just use this as an excuse to get funding for a new satellite based infrastructure or other alternatives. Moreover I suppose HF is most valuable to the military in crisis regions, where there is no BPL anyway ; ) /ralph |
"Ralph Aichinger" wrote in message ... In rec.radio.amateur.policy CW wrote: As I have written, BPL devices *do* have the possibility to keep out of *some* HF frequencies AFAIK. Ham radio would not be the first candidate for this. Air mobile and military users would be more likely to benefit from it. And maybe it is a different perspective here in Austria, as our military has a lot less influence on our society. We've got utilities actively deploying this stuff, and while it is far from being everywhere, it is a real threat in some areas. I suppose they could not care less about implications of BPL for the military. They just do good lobbying, and they have shown their political influence in many issues in the past. Don't count too much on the military. They might just use this as an excuse to get funding for a new satellite based infrastructure or other alternatives. Moreover I suppose HF is most valuable to the military in crisis regions, where there is no BPL anyway ; ) /ralph Will BPL have the same effect on military radio as it has on radio hobbyists? Don't they have spread spectrum capability which is highly resistant to interference? Frank Dresser |
"Brenda Ann" wrote in message ... Thing is, BPL is also spread spectrum.. would not two spread spectrum systems on the same bands interfere with one another?? I don't know alot about spread spectrum, but it's my impression that the receiver and transmitter are in sync. If the interference doesn't match the expected synchronization, the receiver ignores it. Also, the bandwidth of spread spectrum is so wide that spread spectrum operations would have to overlap, otherwise there would only be a few allowable channels. But, any spread spectrum experts out there are free to correct me. Frank Dresser |
They probably do but not in widespread use nor is it likely to be. They do
also have the capability to replace most of that HF traffic by satellite. They did, at one time, start to scale back the HF ops in favor of satellite but decided that was a bad idea from a reliability standpoint. They do have the satalite capablity but maintain HF to. The military, in any case, is only a part of the government HF operation. If bpl has the capability of not using certain segments of the band, due to the amount of space that would have to be left alone, the bpl spectrum is going to be pretty holy. In any case, I really don't think it is a viable technology, I seriously doubt it will be the major rf disaster that some are saying it will be and I don't think it will last long if it gets off the ground at all. "Frank Dresser" wrote in message ... Will BPL have the same effect on military radio as it has on radio hobbyists? Don't they have spread spectrum capability which is highly resistant to interference? Frank Dresser |
Ralph Aichinger wrote:
In rec.radio.amateur.policy Frank Dresser wrote: When I wrote "vunerable BPL is to interference", I meant how outside sources of interference would effect the performance of BPL. Sorry if I wasn't [..] If you know where this is all explained in depth and well documented, please point me in that direction. I don`t know the details, but here in Europe several pilot projects were basically stopped and several larger companies got out of that technology again, after trying to hype it for several years. I do not know if this is due to unreliability or due to other factors, but it *seems* to have worked better in the lab than in the real world. If enough problems make it too unreliable and/or expensive, this might be the easiest way out. I wonder if the lab has defective transformers that spew out rfi? I wonder if the lab regulary simulates lightning strikes on the lines carrying BPL? I wonder if the labs simulate the sometimes awful antiquated power lines that the signal would have to go over? - Mike KB3EIA - |
Brenda Ann wrote:
"Frank Dresser" wrote in message ... Will BPL have the same effect on military radio as it has on radio hobbyists? Don't they have spread spectrum capability which is highly resistant to interference? Frank Dresser Thing is, BPL is also spread spectrum.. would not two spread spectrum systems on the same bands interfere with one another?? Yes, but to a limited degree. One characteristic which distinguishes a spread-spectrum (whether frequency-hopping, or direct-sequence) system from a channelized one, is the gradual way the channel signal-to-noise ratio can degrade as more stations are added in the same spectrum space. This "graceful degradation" is in stark contrast to interference in standard single-frequency applications, where a collision of two signals means no link. Think of two different transmitters sharing the same 1000 frequencies. Each "hops" to a new frequency every few milliseconds at most. If both systems use different channel sequences, it's just occasionally that both would land on the same frequency and interfere with each other. And even in this case, the total amount of time where they're mutually interfering is perhaps a millisecond or less. So the extra signal sharing the frequency has mostly the effect of making the channel a tiny bit noisier for all users, but not to blot out other signals. As you add more and more spread-spectrum stations, the probability of a "channel collision" of course increases. However, by carefully choosing the sequences and making sure they don't accidentally "lock horns" in synch for a while following the same sequence of frequencies, the quality of the link degrades slowly with each new station. I suspect this "graceful degradation" property of spread spectrum is more of a driving force than the potential security and stealth that this system provides. It allows more users to share the same small frequency slice, than would be possible if you just put narrow-band FM equipment and jammed them together as close as possible. Funny how often unexpected benefits spin off of basic research. Here's to renewing science and basic research. Not everything important to business can be measured in quarterly profits. Our competitors, who seem to get this better than a lot of US companies do, will eat our lunch for us if we don't start thinking long-term again. IBM and HP "get it". It's Congress that we need to wake up next. :) -- Ross |
You're right about that. Unfortunately, the standard business plan is to
make as much as you can in the short term and then dump the company. They have no interest in anything that won't pan out in 6 months. "Ross Archer" wrote in message ... Our competitors, who seem to get this better than a lot of US companies do, will eat our lunch for us if we don't start thinking long-term again. IBM and HP "get it". It's Congress that we need to wake up next. :) -- Ross |
"CW" wrote in message news:uca3b.278911$uu5.62460@sccrnsc04...
They probably do but not in widespread use nor is it likely to be. They do also have the capability to replace most of that HF traffic by satellite. They did, at one time, start to scale back the HF ops in favor of satellite but decided that was a bad idea from a reliability standpoint. They do have the satalite capablity but maintain HF to. The military, in any case, is only a part of the government HF operation. Right: Didja ever add up the number of published MF/HF freqs just the Coast Guard and the HF air traffic controllers use?? And those are just a few of the published gummint-used freqs. Then come who the hell knows how many unpublished freqs also used by other civil gummint types. If bpl has the capability of not using certain segments of the band, due to the amount of space that would have to be left alone, the bpl spectrum is going to be pretty holy. It would be one big hole, "selective BPL interference" is a ridiculous and completely unworkable concept. In any case, I really don't think it is a viable technology, I seriously doubt it will be the major rf disaster that some are saying it will be and I don't think it will last long if it gets off the ground at all. If it's allowed to get off the ground at all a huge amount of damage will be done even if it does eventually peter out. The closing the gate after the cows get out syndrome, etc. As far as BPL being an RF disaster is concerned I've travelled twice to one of the BPL pilot areas specifically to listen to the stuff hands on. Been there, done it myself and I need to tell you that yes BPL is a potential HF/VHF disaster which needs to be squashed *before* it even gets off the ground. Anybody who belives otherwise needs to get off their butts and away from their keyboards, pack up a rig and actually go listen to stuff before they spout off about it. Brian Kelly w3rv |
"Frank Dresser" wrote in message ...
"DickCarroll" wrote in message om... "Frank Dresser" analogdial@worldnet Hey Frank, where'd you ever get the idea that radio *isn't* open to the public? I never knew anyone whatever who wanted a ham radio license who was barred from getting one. There is a small matter of qualifying for it, of course, as there is in every endeavor where others can and will be impacted when the licensee knows not which way is up. But it has always been open to all comers. OK, amateur radio is open to the public. But nearly all amateur radio activity is either contacts between hams or some sort of test. I'm under the impression that amatuers broadcasting what might be considered entertainment programming to the public is banned. Am I wrong about that? No, sounds accurate to me. Now if you're talking "open" like CB is open, that's a horse of an entirely different color. Dick More like pirate radio. I've heard some very entertaining stuff, and I hope to hear alot more. I know that time can be bought on an independent broadcaster, but I'd really like to know why what Alan Maxwell and the other do is illegal. I think hobby broadcasting would bring alot of positive interest to SW radio. As always,it's a $$$$$ thing, of course. |
DickCarroll wrote:
"Frank Dresser" wrote in message ... "DickCarroll" wrote in message om... "Frank Dresser" analogdial@worldnet Hey Frank, where'd you ever get the idea that radio *isn't* open to the public? I never knew anyone whatever who wanted a ham radio license who was barred from getting one. There is a small matter of qualifying for it, of course, as there is in every endeavor where others can and will be impacted when the licensee knows not which way is up. But it has always been open to all comers. OK, amateur radio is open to the public. But nearly all amateur radio activity is either contacts between hams or some sort of test. I'm under the impression that amatuers broadcasting what might be considered entertainment programming to the public is banned. Am I wrong about that? No, sounds accurate to me. Now if you're talking "open" like CB is open, that's a horse of an entirely different color. Dick More like pirate radio. I've heard some very entertaining stuff, and I hope to hear alot more. I know that time can be bought on an independent broadcaster, but I'd really like to know why what Alan Maxwell and the other do is illegal. I think hobby broadcasting would bring alot of positive interest to SW radio. As always,it's a $$$$$ thing, of course. The National Association of Broadcasters has lobbied hard to keep hobby broadcasting illegal, even on SW. They say that the AM and FM bands are too crowded, and that's true, but SW is wide open. Of course they're really concerned about innovative programming taking over market share. If hobbyists were allowed on SW the radios would fly off shelves because there'd finally be an alternative to automated corporate programming. (I know for a fact that Clear Channel controls six or seven radio stations in the San Francisco market, each carefully programmed as not to compete with each other.) |
In article ,
Frank Dresser wrote: [snip] Will BPL have the same effect on military radio as it has on radio hobbyists? Don't they have spread spectrum capability which is highly resistant to interference? Frank Dresser Spread-spectrum is highly resistant to narrowband interference. BPL develops wideband interference. What the military depends on is the physics that any remote jammer trying to create wideband noise would need to be immensely powerful, because a wide band of loud-at-a-distance noise would have to have substantial energy at every frequency. BPL defeats this by putting the transmitting antenna very near the receiver, so the noise source need not be powerful to be loud at every frequency. -- R F Wieland Newark, DE 19711-5323 USA 39.68N 75.74W Icom R75 Heathkit GR-81 Inverted-L in the attic Reply to wieland at me dot udel dot edu |
"Robert F Wieland" wrote in message ... In article , Spread-spectrum is highly resistant to narrowband interference. BPL develops wideband interference. What the military depends on is the physics that any remote jammer trying to create wideband noise would need to be immensely powerful, because a wide band of loud-at-a-distance noise would have to have substantial energy at every frequency. BPL defeats this by putting the transmitting antenna very near the receiver, so the noise source need not be powerful to be loud at every frequency. -- R F Wieland Newark, DE 19711-5323 USA 39.68N 75.74W Icom R75 Heathkit GR-81 Inverted-L in the attic Reply to wieland at me dot udel dot edu That's what I'd expect. But I don't know if the BPL system will dirty enough, or close enough to significantly interfere with military communications. I suppose the military has sent people out to take readings like Ed Hare did. Anyway, I'm thinking the biggest threat to BPL isn't outside opposition, but the spikey wideband trash normally found on power lines. That's it! BPL is a wives' conspiracy to get their husbands to start vacuuming the freakin' carpet! Frank Dresser |
On Wed, 27 Aug 2003 09:57:46 +0000 (UTC), Ralph Aichinger
wrote: And I think military users could change to VHF or UHF, even sat communications anyway if they wanted. They could also keep BPL out of special areas. I doubt military users in suburban environments give a damn about HF. ARINC *has* filed comments. Apparently, one of their receive sites near San Francisco was severely affected by some Part 15 equipment in a house nearby. One of their 3 MHz frequencies was rendered unusable. The NTIA will step up to bat for the military and government HF users. Take care, Dave David Moisan, N1KGH, SKYWARN Invisible Disability: http://www.davidmoisan.org/invisible_disability.html GE Superradio FAQ: http://www.davidmoisan.org/faqs/supe.../gesr_faq.html Sangean ATS-909 FAQ: http://www.davidmoisan.org/faqs/sangean/ats909faq.html |
| All times are GMT +1. The time now is 01:45 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com