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"Jim Hampton" wrote in message ... "Dee Flint" wrote in message ... wrote in message ups.com... wrote: [snip] The article also accepts without question the idea that fast internet access is a necessity for all Americans and their communities - another Bush Administration bit of rightthink. Actually this would be more of a liberal idea. It surprises me that a Republican administration would buy into this. Thanks for posting the link. Anybody besides me and the original poster actually listen to it? 73 de Jim, N2EY Dee D. Flint, N8UZE Hello, Dee Liberal? Pushing for more money for power companies? Please forgive my ignorance, but if I follow the money trail, it leads to big business (monopolies, at that). 73 from Rochester, NY Jim AA2QA Liberal because it is being pushed as every having a "right" to broadband. Yes follow the money and it leads to as many liberal business men as it does conservative ones. Dee D. Flint, N8UZE |
wrote in message ... On 17 Aug 2005 09:55:16 -0700 wrote: | The "notching" solution is simple: Their BPL system does not use | frequencies that are also ham bands. Whether it works or not is an open | question. What about MARS and SWL frequencies? | - BPL is a "last mile" delivery method, not a complete system. Still | needs a 'head end' I've seen pictures of these units on primary (12 kV) lines, so by "last mile" this must mean more than just the drop into the home. | - BPL bandwidth is shared between users on the same line, so as your | neighbors sign up and use the system, your performance degrades. On what line? The primary (12 kV) or the secondary (120/240 V)? | - There are other technologies (like Wi-Fi) which can do the same job | without all the fuss and bother. These are on 12cm and 5cm from what I have heard. | - The big danger of BPL is that it turns the whole idea of spectrum | protection and allocation upside-down, and sets a bad precedent. It can also be susceptible to ham transmissions, which will unfairly blame the ham radio operator as the cause of networking failures. It will also be susceptible to interference from natural sources such as lightning and other manmade sources such as occur with many electrical devices. It would be quite easy to have a case where the computer power supply, computer monitor, television, fluorescent lights, etc could cause a degradation of the service. Dee D. Flint, N8UZE |
Dee Flint wrote:
"Jim Hampton" wrote in message ... "Dee Flint" wrote in message ... wrote in message ups.com... wrote: [snip] The article also accepts without question the idea that fast internet access is a necessity for all Americans and their communities - another Bush Administration bit of rightthink. Actually this would be more of a liberal idea. It surprises me that a Republican administration would buy into this. Doesn't surprise me at all. Thanks for posting the link. Anybody besides me and the original poster actually listen to it? Hello, Dee Liberal? Pushing for more money for power companies? Please forgive my ignorance, but if I follow the money trail, it leads to big business (monopolies, at that). Exactly. Liberal because it is being pushed as every having a "right" to broadband. I don't hear that in the article at all. What *is* mentioned is the idea that the town needs it for their economy. Yes follow the money and it leads to as many liberal business men as it does conservative ones. Sorry, Dee, I don't see that at all. BPL is basically bad science and bad engineering, pushed by the promise of being a quick "high-tech" fix. Fits right in with the current administration's attitude towards science and technology. The pollution angle alone shows it to be a bad idea. 73 de Jim, N2EY |
From: "Jim Hampton" on Wed, Aug 17 2005 4:29 pm
wrote in message Jim Hampton wrote: wrote in message Power lines were never meant to carry HF communication signals. No kidding?!? From whom did you pick up that factoid? :-) They're lossy at HF because they radiate! The whole concept is deeply flawed. By allowing BPL systems, FCC is setting a very bad precedent by saying it's OK to pollute the electro magnetic spectrum with noise, even if there are viable alternatives to the noise-producing technology. A couple of points he First, the FCC does NOT "allow" Access BPL existance. Access BPL systems are (note carefully) UNINTENTIONAL Radiators. Secondly, the FCC has never ever established any "radio service" about or for any Broadband Over Power Lines concept. BPL is a WIRED system; i.e., NOT an intentional radiator of RF. Thirdly, the FCC DOES CONTROL RADIATED RF LEVELS AND TO ESTABLISHED SPECIFICATIONS NOW IN TITLE 47 C.F.R. That radiation level HAS been quantified and put into an Order that did appear both in the Federal Register and at the FCC website under the Office of Engineering Technology link. It wasn't under the Wireless Telecommunications Bureau page nor the Amateur radio page under that (there hasn't been any new link on the amateur page there since 2002). The NOI (Notice Of Inquiry) of the FCC that caused this recent flap and furor was NOT about the existance of BPL as any service...IT WAS ABOUT MEASUREMENT METHODS TO DETERMINE ACCEPTIBLE WAYS TO MEASURE THE RADIATION. The OET knew damn well that BPL would radiate. But, they could NOT LEGALLY STOP BPL from existing. All they could do is establish a legally-acceptible MEANS OF MEASURING THAT EXPECTED RADIATION. Well, by limited interference, I am suggesting that BPL be limited as any other unintentional radiator. It IS. One has to scrounge around the FCC webiste a bit to find it, but it IS there. I do hear your point and it is well taken. We do *not* need "only" a 10 dB increase in noise in general LOL Nobody does, but it has happened. Listen to the "ISM" bands and the DSSS and stuff there does raise the noise floor. However, the occupancy of those ISM bands is nearly ALL that mode and those users coexist peacefully. Also, as we are well aware, no filter is perfect, whether a notch filter or a bandpass filter or any other filter. Also, filters introduce distortion into the signal. Irrelevant. Those "notch filters" can't erase MOST of the frequencies on HF. The "licensed users" and the UNLICENSED listeners are spread over most of the HF spectrum. So, it remains to be seen if the power companies can come up with a BPL with very limited impact on licensed services. I do have my doubts, but am only suggesting that *if* they can prove a system can produce very low noise in the airwaves, then it might be worth a try. That is a *big* if. Many, many things ARE possible. The last 109 years of the total existance of radio have shown that. However, TRANSMISSION LINES of signals are technology that goes back BEFORE the "birth" of radio in 1896. Lee de Forrest, the inventor of the three-element vacuum tube, was studying transmission lines academically before his "audion" experiments. As far as our present-day technology knows (and that is considerable), transmission lines with lots of discontinuities will radiate; the TEM field won't be nicely contained. Given that the ordinary 60 Hz power distribution lines are chock full of discontinuities and changes in conductor size and spacing (thus a change in characteristic impedance where that step is a discontinuity), those power transmission lines WILL RADIATE RF. That is inevitable. IF and ONLY IF the electric power distribution system was designed and REBUILT to known transmission line standards at HF-VHF could such a wired BPL system be tried out for minimum interference. was not |
In article . com,
wrote: The "notching" solution is simple: Their BPL system does not use frequencies that are also ham bands. Whether it works or not is an open question. But how long will that last? Here in Israel we call it the "boiled lobster" effect. A live lobster placed in a pot of cold water is happy. As the water gets hotter it falls asleep. It never realizes it's being cooked. This what will happen with BPL. By the time you realize that it's taken over the ham bands, it will be too late. That's why I'm boycotting Google, they with two other companies invested $100,000,000 in BPL. Geoff. -- Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM IL Voice: (077)-424-1667 IL Fax: 972-2-648-1443 U.S. Voice: 1-215-821-1838 Support the growing boycott of Google by radio users and hobbyists. It's starting to work, Yahoo has surpassed Google. |
A good source of information about BPL is Anthony Good's FAQ website
at: http://www.qrpis.org/~k3ng/bpl.html |
wrote:
On 17 Aug 2005 09:55:16 -0700 wrote: | The "notching" solution is simple: Their BPL system does not use | frequencies that are also ham bands. Whether it works or not is an open | question. What about MARS and SWL frequencies? That's unclear. If covered, the result is more notch than coverage. | - BPL is a "last mile" delivery method, not a complete system. Still | needs a 'head end' I've seen pictures of these units on primary (12 kV) lines, so by "last mile" this must mean more than just the drop into the home. What is typically done is that fiber or other highcapacity communications is brought to a point (the injector) near a bunch of customers. Then the signals are converted to the frequencies used by the BPL system and put on the medium-voltage distribution line. (Note that a distribution line and a transmission line are not the same thing to powerco people). At each stepdown (service) transformer, there's a coupler to take the signals around it, because such transformers are very lossy at BPL frequencies. They're intentionally designed that way to keep noise and surges off the service drops. Which means that the couplers will bring HF noise and such into customer's houses. The distance from the injector to the customers served is typically measured in hundreds or thousands of feet, not miles. The MV distribution lines are not used forlong- or even medium-distance BPL transmission - too lossy. | - BPL bandwidth is shared between users on the same line, so as your | neighbors sign up and use the system, your performance degrades. On what line? The primary (12 kV) or the secondary (120/240 V)? Both. Let's say you have an injector site that feeds a few thousand feet of MV line, and there are a dozen or so transformers on that line, each with its own coupler, and customers. The available bandwidth is shared by all the customers on that injector. If there's (say) 5 mbd available from that injector and only one customer is active, s/he gets all 5 mbd - 100 times the speed of dialup! But if there are 20 customers active, they all have to share, and may get only 250 kbd each. Which is only 5x the speed of dialup! (Numbers are only for the purpose of illustration) It's like the situation experienced by people with a DSL or cable modem connection and multiple computers in the house all online at the same time, except that you have to share with the whole neighborhood, not just Junior upstairs gaming. | - There are other technologies (like Wi-Fi) which can do the same job | without all the fuss and bother. These are on 12cm and 5cm from what I have heard. Yup. | - The big danger of BPL is that it turns the whole idea of spectrum | protection and allocation upside-down, and sets a bad precedent. It can also be susceptible to ham transmissions, which will unfairly blame the ham radio operator as the cause of networking failures. Once word of that gets around, hams may be blamed even if they're *not* the cause! Ultimately the rise and fall of BPL will depend on whether it can compete in the marketplace with DSL, cable, and other methods. Hopefully it cannot. While hams, ARRL, IEEE and others were not able to completely stop BPL, neither were BPL proponents able to get the rules changes they wanted, either. And actions by groups like ARRL spread the word of the BPL threat early on, rather than waiting until the systems gained a foothold. There have been several instances where test BPL systems were shut down as being impractical. Some municipalities that were looking at BPL eventually said "No thanks" due to the issues raised. Meanwhile, the competing broadband solutions become more available and more affordable. 73 de Jim, N2EY |
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Dee Flint wrote:
wrote in message ups.com... wrote: [snip] The article also accepts without question the idea that fast internet access is a necessity for all Americans and their communities - another Bush Administration bit of rightthink. Actually this would be more of a liberal idea. It surprises me that a Republican administration would buy into this. There is a lot of money to be made - even if it doesn't work very well. Democrats have *not* cornered the market on bad ideas! 8^) That is why I call it "faith based engineering". It *sounds* like a great idea to use all those electrical lines to run the signals. Reminds me of when I was a little kid, and though that we could fill the cars gas tank by driving in reverse..... 8^) - Mike KB3EIA - |
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