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From Ed Hare (W1RFI) of the ARRL on BPL replies to comments;
(repost from QRZ) What I believe to be most important at this point is that the FCC get a wide range of input that is not all "ARRL" material. Analyzing ARRL's material is fine, but it really does need to appear as an individual contribution, not just a "me-too." That is why ARRL hasn't put out a "form letter" to be used, because especially in the NOI stages, this is not a vote. I have seen a number of excellent posts here outlining things I hadn't thought of. Over this evening and into early next week, I intend to start reading the various company and organizational filings in detail. Naturally, I will put together a technical recommendation to the DC guys, who will use them to develop ARRL's "political" position and to write the ARRL filings. Because this is a rulemaking process, all the major players tend to keep their "stuff" close until the last day, to give those with different positions less ammunition. So, unfortunately, I am not sharing what I have learned with even the amateur community, except in the most general terms. I can say that I just got back from a 1300-mile drive to several of the test areas, and the ARRL article used a description I considered carefully before being quoted -- the interference to HF that I observed was devastating. The APPA folks demanded that any claims of interference be proven. I believe we can give them exactly what they wanted and do just that. It is not just amateur radio that is at risk here, but any use of HF that operates near BPL installations operating on their frequencies at the limit of the present FCC rules cannot help but hear the BPL signals loud and clear. I had done calculations of what to expect, and the system that operate at the present limits did just what I knew they would. The real issue is interference. The BPL industry is claiming that there is no interference problem, but where are THEIR calculations? Where are their interference studies? They have offered no information about the frequencies their systems use, no information about what field strength they measured in their Part 15 verification tests. The only basis on which they make that claim is that they have "no reports of interference" and by pretending all the overseas amateur studies don't exist, and claiming that there has been no interference worldwide. Some did provide some power levels, of -50 dBm/Hz. This power level results in a conducted signal level of 48 dB higher than the present limits for conducted emissions for most other devices, upsetting the present order by a factor of 70,000. How can this not have an effect. They want to add 10 dB, so their conducted signals would be almost a million times more powerful than the present conducted emissions limits. Ever hear a neighbor's computer system? Want to multiply that by a lot? |
#2
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"Dick Carroll;" wrote in message ...
Rob Kemp wrote: It is not just amateur radio that is at risk here, but any use of HF that operates near BPL installations As well as any other radio system operating over a wide area up to the 80 MHz limit planned. Public safety comes immediately to mind since I worked in that fielf. You worked in that filth? I know that a number of states presently still use low band VHF for state police communications using direct car to base systems as well as many crossband repeaters with receivers covering considerable areas operating on frequencies between 40 and 50 MHz. Since you are an Extra in that filth, you might want to suggest that they move. I worked as a field engineer in such a system and RF noise was an ongoing problem. I'm sure Roosterpoop, MO is a hot rf environment. And with the FM systems in use, often the noise will simply keep the squelch closed and the recever won't be aware that the transmitting station is attempting a call. That's bad news. I recall one such particularly troublesome repeater where that would occur and by the time I could drive to the repeater site the "phantom" problem was gone. After several unproductive tries, I finally found the source of the noise- a welder in a shop about a half mile from the repeater site which welded only ocassionally, and those times just happened to coincide with the repeater desense problems. I thought all spark transmitters had to be registered. We wound up relocating that repeater because of it. We? If that sort of situation can virtually shut down a single low band repeater I can only simagine the sort of wide area problems could be caused by BPL. Dick Just simagine it. |
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