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.