Jim,
If the noise is higher during a rain and quiets at least some while dry, that
usually indicates insulator dirt or breakdown. Have them replace it anyway.
If it has arced in the past it will be prone to arc in the future.
Noise will travel further the lower the frequency. So, if you are not hearing
it on 10 meters or VHF then the source is likely further away.
The other thing that can throw you off is that *nodes* of an arc noise increase
will occur away from the source on a repeating basis giving a false sense of
where the problem is.
If you have a directional antenna on VHF, you are more likely to be able to
find the direction of the source as VHF antennas usually have a tighter
beamwidth. I have transverters for 2 and 432 with high gain yagi's where I can
use the AM mode on my HF radio to listen.
Jim - KR9U
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Jim Murray
via Topband
Sent: Monday, October 26, 2015 1:30 PM
To: topband@contesting.com
Subject: Topband: Re. RFI - lots of it
Noise has decreased today. We have had off and on showers up to about 24 hours
ago and today clear and dry, barometer up. Evidently wetness increases the
noise. I checked nearby poles etc. and nothing concentrated near the poles.
Loudest I get is along and beneath a junction where lines from our home and
lines coming from a building across the road meet. Somewhat of a birds nest of
wire right there. I also found that the garage door opener (when not it use)
also generates some noise but not strong enough to reach very far. Also,
thanks Jim. I read your article and I have a fairly good grounding and bonding
situation. The biggest difference is that I have a grounding bar (solid
copper, thick strip not a grounding bar that is pounded into the ground)
inside attached to the operating table that everything is attached to and bar
is earth grounded. Pretty much all the same setup I've used for years although
I didn't have the rfi problem. One problem I see that may com
e up is if the noise level is down at hf and the power company checks at vh or
uhf, which ever they do I don't think they will pick it up (unless it rains).
Thanks again to all for the help.Regards,Jim/k2hn _________________ Topband
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