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Broadband Over Power Lines vs. Radio Relayers
amaiman writes "Recently, broadband Internet access has been increasing around the country. These broadband signals, while providing Internet access to remote communities that would normally not be able to receive broadband, are causing enormous interference to the radio spectrum. This article details some of the problems, and a video available on the American Radio Relay League's (ARRL) site shows exactly how much interference the broadband power lines can cause. Detailed information is also available on the ARRL site."
Note that it's only a *very* small subset of the ham community that's even considering deliberately jamming BPL. Most hams are considerate to a fault, and wouldn't retaliate like that.
But for now, if you need to use 1500 watts to make a contact, it's legal for a ham to use 1500 watts to make that contact (on most bands), even if it causes problems for BPL. The law says you need to use the minimum amount of power to get the job done, and most hams do that. But if you need 1500 watts to get the job done, then you can do that.
(For the record, I'm AD5RH. And I don't have any equipment capable of putting out over 200 watts.)
Look out your window - every amateur radio operator who lives within a couple hundred yards of a powerline will be affected. Not only that, but, according the the ARRL site, rural emergency radio communications (Fire Department, Ambulance, etc) will also be affected. Don't forget, also, that the frequencies that we're talking about are used by amateurs to provide emergency communications during natural disasters, health and welfare traffic, as well as comms during public events like marathons, bike races, parades, etc.
BTW, it's not a matter of pumping up the transmit power either. It's on the receive where BPL causes the biggest problems. You're already trying to listen to a whisper in crowd, and BPL is like an obnoxious car salesman with a bullhorn.
Shortwave radio communication over any long distance (commercial, military and hobbyist) often deals with weak signals. Each broadband power line adds to the background noise cumulatively raising the problem. One power line won't trash your TV signal (unless you are very close), but each one adds noise until all you have is snow.
Its like people talking in the background - a couple of people don't do much harm but when you try and talk across a room full of quietly talking people two things happen
1. The cumulative background noise reduces the signal
2. You turn the volume up (as the amateur radio people will have to and although entitled too don't wish too because it causes other users problems)
When you turnt he volume up, they all have to talk louder, so you get a fight between high and higher BPL power (to avoid radio wiping out internet, and higher and higher radio power for the same reason). At which point nobody can communicate usefully and lots of third parties are harmed.
HF interference isn't just an amateur radio problem either - you might well find you get 802.11 dead zones if you are near a power line using it. You may not be able to use radio controlled toys in an area with too many power lines and so on. Finally HF is essential to things like flying medical services and some rural communcation systems.
It all gets quite messy when this happens because good radio practice is the lowest possible power. The lower the power you can use the more people can use the same frequency. If everyone has to use 1KW then you'll get a lot less frequencies.
I'd also say their description of the FCC is in tune with its historical decision making - just look at the monopolisation of US commercial radio and the continued unneccessary exclusion of most small transmitters which could exist and other countries have proved are not a problem. Of course BPL background noise might well wipe out the scope for very low power radio stations too.
BTW: BPL trials in the UK (way before the US) were shelved for several reasons but intereference was a big one.
It shouldn't be insoluble - one nice property of radio is that if you can get the BPL encoding frequencies high enough then the interference problems become much less of an issue.
(PS: I defy you to find a radio astronomer who won't use expletives when asked abtut BPL..)