[RFI] Short wideband noise bursts 3-100+ mhz
aaron at campusactivism.org
Tue Sep 24 18:35:07 EDT 2013
I've got very short noise bursts coming from a nearby house. Unlike my
other noises (power supplies, general hash) this is the first one that I
can really narrow down - as I can hear it from 3-110 mhz and it is
probably coming from one of six houses. The noise has a range of
several hundred feet. On my antenna it is around S5-S7.
It is extremely broadband. I'm guessing that is has a 100 mhz+
bandwidth like a spark gap transmitter.
It is probably audible above 110 mhz, but I cannot hear it in FM mode
and the air band is the highest band that my scanner can get in AM.
It sounds like a click in AM. It is on 24 hours. It is occurs roughly
every second, but not in a regular pattern (ranges from several per
second to a gap of 3-5 seconds).
I'm guessing I don't hear it below 3 mhz because other noise dominates
at those frequencies. However I am surprised that it doesn't come
through at all around 500 khz which often has a low noise level. So it
is possible that the signal is weaker at lower frequencies.
Any ideas what it could be?
For a while I was thinking it could be lightning, but lightning bursts
are much longer and don't continue into the higher frequencies.
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