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[RFI] 30m noise problem

To: <RFI@contesting.com>
Subject: [RFI] 30m noise problem
From: "Lee K7TJR" <k7tjr@msn.com>
Date: Wed, 21 Apr 2010 20:04:32 -0700
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>
>>  I've been using a portable sw radio in the immediate neighborhood tuned
to 10mhz, but it's difficult to hear the fine structure of the
modulation with only the am detector that is available; that is,
everything just sounds like line noise. In essence, I'm not sure if I'm
listening to my interference or general line noise of which there is a
goodly amount.<<

Jerome, To me your noise clearly sounds like a 60Hz line noise problem.
  It also sounds very much like a worn out sodium street light that is trying 
to fire.
    I would look for a street or parking lot light that either does not work at 
all or was very dim near your shack.
  Once you get close with a BC radio to an offender you should easily hear the 
hum just like your A.M. mode on 30 Meters.
I looked at the A.M. waveform on a scope and The "fine structure" of the noise 
you see may just be ringing in your receiver filters due to the very large and 
sharp edged 60 Hz noise spikes. The A.M. mode is showing you the real story.
Lee  K7TJR   OR 
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