LF: Re: Carriers

[DL4YHF@aol.com]

Hi Mal and Alan,

I can strongly confirm such QRM from modern TV sets. That also seems to be 
the reason why some days I "don't have ears" when operation from DF0WD. 
On a spectrogram, you can see the 50- or 100-Hz-spaced lines drifting around 
slowly.
Also confirm the range of these nasty carriers: they can indeed exceed the 
range of 100 yards (~meters). The clubstation DF0WD is about 150mtrs away 
from the next house, but a part of QRM seems to correlate with the TV prime 
time. On the waterfall its impressive to see a group of carriers disappearing 
instantly after the main evening news at 20:15 local.

I guess most of the QRM travels over the mains supply lines. I already 
considered building a battery-powered remove RX with a 70cm-FM-link to the 
main station (using a cheap 70cm-LPD handy). The problem is finding a quiet 
remote RX side where the RX cannot be vandalized or stolen.

As alternative, I am very curious about Steve's and Rob's noise canceller 
experiments. IMO, cancelling more than one QRM source is a tough job.

Good luck to all,
  hope to c u  on 136kHz,
    Wolf  DL4YHF.