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Re: Topband: RFI

To: topband@contesting.com
Subject: Re: Topband: RFI
From: fmoeves <fmoeves@twc.com>
Date: Thu, 25 Jun 2020 16:12:37 -0400
List-post: <mailto:topband@contesting.com>
Mark Frank Guillermo and Jerry,Thank you all for the great ideas. Looks like I 
have my work cut out for me. I think it's coming from the south. My South 
Beverage picks it up the strongest North Beverage still strong but little 
weaker. On 40m I have 2 full wave loops and the n/s loop picks it up very 
strong. My neighbors already think I'm crazy. So it's really going to be crazy 
around here when I walk around the streets with a 4' loop. Thanks 73 Fred 
KB4QZH 
-------- Original message --------From: K4SAV <RadioXX@charter.net> Date: 
6/25/20  3:10 PM  (GMT-05:00) To: topband@contesting.com Subject: Re: Topband: 
RFI Power pole noise can be difficult to find with a portable receiver that is 
not directional.  It's also difficult to find when all you have is an 
ultrasonic detector because those have to be pointed right at the source to 
hear anything..  Power lines make a good antenna for radiating power pole 
noise.  Often the wires act like a long wire antenna and that can sent the 
noise for a long distance in the direction the line runs.  My record for that 
with S9 noise at home on 160 has been 3 miles to the source.  The source was 
very big.To get started searching in the right direction try locating the 
direction with a rotatable antenna from home.  A 6 meter Yagi does well 
usually. Then when you head off in the right direction, you need an AM receiver 
with a directional antenna, something like the MFJ-856 which is a 135 MHz AM 
receiver with a 3 element Yagi. That will get you within a pole or two.   Other 
receivers can work too but it really needs to be on AM.  Then an ultrasonic 
detector can be used to identify the part on the pole that is the source. I use 
a homebrew one but MFJ also makes one, the MFJ-5008.After you think you have 
found the source, try to verify its characteristics with what you are hearing 
at home.  You don't want to send the power company to fix something that is not 
your problem.  I often find lots of noise sources that I don't hear at 
home.Jerry, K4SAV_________________Searchable Archives: 
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