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On Apr 26, 5:49*am, dave wrote:
Brian Gaff wrote: I think that there are items that are known to be a problem. Power line adaptors that shove broadband signals down the mains to save the user running a couple of wires are the worst thing, as although they have notches at the ham band frequencies, they do not for most of the rest. They do bty their mere design, send *rf signals down the mains supply. However although this contravenes the british electromagnetic interference specs, the EU directive that allows these devices gives them a waiver. * The switch mode supplies for things like laptops, mobile phone chargers and small domestinc devices like answering machines, ar often made in china, and many have no parts inside to snuff out the *spikes they send down the mains wiring. They probably did at the start, hbut the Chinese are always looking for cheap ways to do things, and who ever opens the devices after the first run is made? Plasma tvs use some form aof hf pulsing of the *cells or pixels to counteract the *pulsating effects at low brightness they are often known for in early samples, and this shoves out huge amounts of wide band noise. The problem of course is that the devices to null out what used to be a single source no longer really work when the transmission *is coming from mains wiring in an adjacent house. * Brian At least in the USA a ham license gives one legal standing to demand the interferer stop.- Hide quoted text - - Show quoted text - Yeah, but - that's sort of like asking a deeply sleeping fatso to quite snoring. |
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