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Old July 4th 06, 05:36 PM posted to rec.radio.shortwave
Mark Zenier Mark Zenier is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 237
Default local interference from cable or television

In article ,
weatherall wrote:

During a few listening sessions, I have noticed that when I can hear the
television turn on in the apartment below me, local interference becomes
much louder. Have any of you dealt with this issue in the past? Which
component generates the interference - the wiring, the cable box, or
the television? What remedies can I propose to my neighbors?

I'm using portable radios (Sony ICF SW7600GR, Eton E5, Kaito 1102) with
the whip antennas, and typically the antennas are oriented horizontally.


Usually, it's the horizontal scan circuits, which also double as
a large part of the power supply. This usually shows up as a noise
peak at twice the scan rate. For older TVs, about every 31.5 kHz.
(And if a TV is tuned to a dead channel and is only getting snow (and
doesn't go blue screen), it will put random noise over all the bands).

Since these circuits are dealing with several 10s of watts and have
a lot of short pulse waveforms and high voltages, there's not too
much hope. You could try a loop antenna.

Mark Zenier
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