Hi I am interested in all the comments. Like me Mike being rural probably
has an overhead "drop". He describes the ADSL as running "all round the
house". His sons run a business from the premises and I think the problem is
more likely to be network cables and servers which are running 24/7. He says
the QRM definitely peaks from the house on his loop but is so wide spread it
cannot be completely nulled, which suggests an extended source. It may be of
course he has a duff ADSL filter, I have heard of that happening.
I have neighbours either side with broadband and I am not aware of any
problems on 500k, but what I did notice was a horrendous noise in the middle
of the band when the video recorder was sitting on timed record and the TV
was switched to AV. I often do this to avoid missing programs or missing
them due to a phone call in the middle. It would seem that whilst not
receiving a signal, but producing a raster (blank screen with an "AV"
legend) there is a large comb of frequencies at about 502. I am guessing
that without a signal to lock it, the line oscillator free-runs a little
above 15.625kHz. Putting my TV on standby or OFF kills the noise.
Cheers de Alan G3NYK
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