Anders Johansson wrote:
James Knott wrote:
Ken Schneider wrote:
I have been reading articles lately of broadband running through the power cable and being tested in some areas. You may not need to invent the barbed wire modem after all.
You may have to write new laws of physics, to prevent interference issues. BPL pollutes the radio spectrum.
For internet over power cables? Not at all, that's been around a long time. The power company in my home town were runnnig tests with that 5 or 6 years ago. You don't get incredible speeds, but it's quite usable and not *that* slow
The only system that doesn't generate significant amounts of interference is one developed by Motorola, which uses only the low voltage, local distribution wires. Others also use the higher voltage lines over longer distances, which are far worse. However, all BPL systems generate radio frequency energy and send it over lines that were never designed to carry such signals. As a result, they leak like a sieve, both in and out, which means that not only do such systems generate interference, but they're also suscetible to interference from nearby transmitters. While filtering and tuning can be used to reduce interference on specific frequencies, the bottom line is that power lines, when used to carry RF, will radiate some of it. That is impossible to get around, because of the laws of physics. There have been plenty of reports of such interference, to the point that some utilities have withdrawn those services. I suggest you get a receiver that's capable of being tuned over the spectrum used by BPL and see how much interference it actually causes. You might be suprised.