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"Jim Hampton" wrote in message ... Dick, I'm not at all sure who uses what spectrum in the areas where they are testing BPL, but I'd bet coffee for a week that those folks studied the situation carefully before proceeding. Where did they test (I don't know of all areas and I'm asking a sincere question)? The fact of the matter is that the ONLY serious technical studies presented to the FCC in their Notice of Inquiry on BPL came from the good work of Ed Hare, W1RFI, and his colleagues at ARRL. The "access BPL" industry has done essentially nothing but "hand- waving" and ignoring/denying that the problem exists. They want to make $$$ ... and they don't appear to give a damn about the impact on the other users of HF. That they claim that "power wires don't radiate" (when NEC models, as well as plain old common sense, indicate that they do) and that "BPL is a 'point source' radiator" (how one can make that argument when what they are building is essentially a large, distributed antenna system) clearly indicate their deep state of "don't confuse the issue with the facts" denial. The "promise" of BPL is to serve areas that are not served well by cable or DSL. While DSL is not available in all areas due to the distance from the central office factor and the phone companies' slow rollout in areas of lower population density, acccording to the latest statistics I've seen, cable "passes" 97%+ of US households. There are also internet via satellite services available, using dishes like (sometimes the same dish as) satellite TV services. There are also "WISPs" who provide services using more appropriate spectrum in the low microwave bands. The business model for BPL is WAY less than compelling and its technical suitability is poor as well, not only because of interference TO the wide variety of licensed HF users, but also because of the potential for interference to the BPL system FROM those licensed users ... and BPL will have NO claim of protection from such interference. My belief is that consumers deserve a more robust and reliable means of receiving broadband internet services - one that doesn't present the (bi-directional) interference issues of BPL - and that there are a number of such alternatives available already. Did they test a fairly substantial area in the country where they could demonstrate far-flung connections to the BPL, or did they test in densely populated areas that are already served by various broadband connection (where fire, police, emergency, etc. are very likely not on low band VHF)? Ed has a better overall view of the current deployments of BPL, but I know they are few and limited in scope at the moment. Also, FM broadcasting is usually located near large population areas (since signals tend to die off pretty quickly after 40 or 60 miles). This means that if you have BPL in a city, it is unlikely that residents will experience capture effect on the FM receivers since they will be getting *huge* signals on their FM receivers. S9+10 on a VERY short whip (an "Outbacker Joey") is a pretty huge signal to me ... with BPL proposing to go up to 80 MHz, I would think that the FM broadcast band is at relatively low risk, though FM receivers could experience some degree of "desense" if the BPL signal at the front end was strong enough due to proximity. I note the "neon sign" comment in the thread. Neon signs are usually found in cities. The "neon sign" assertion by the representative of PPL (the Emmaus BPL system operator) is *pure* BS ... the signature was SS, NOT a neon sign ... Those test sites are likely located either in a city or in an area where the money interests already checked the FCC site to ensure no low band VHF use by police, fire, ambulance, etc. I think you're giving them FAR too much credit for caring about anything but deploying BPL ... Carl - wk3c |
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