Topband: Top Band power line noise Signature or Fingerprint Techniques

[w2pm at aol.com]

A neat program I use to do that here (and I have TONS of opportunities 
to have to profile the noise) is Zelscope - which runs in Windows and 
uses the soundcard interface you might already have on your rig for 
digital applications, recordings, etc.  You can download a 30 day free 
demo - and later buy the full copy for a whopping 10.00. Oscilloscope 
and Spectrum analyzer and allows you to capture waveforms and save to 
files.  I simulataneously record .wav files of the crud noise to go 
along with the waveform snapshots, or you can Zelscope to watch the 
sound files ..  Together with screen shots of the local weather and 
time, it has been used by me with ARRL and their lab to pursue major 
line issues here in NNJ and get past power company quick answers about 
the noise - "coming from the operator's Bird Wattmeter element or his 
push-on PL259's" ...     See  http://www.zelscope.com/

Pete W2PM

-----Original Message-----
From: Ed Callaway <n4ii at arrl.net>
To: topband at contesting.com
Sent: Tue, Dec 29, 2009 8:35 am
Subject: Topband: Top Band power line noise Signature or Fingerprint 
Techniques


I am pleased to be able to support Carlos' experience with Orlando of
Florida Power & Light's radio (noise) shop.

For some years I operated W4MOT, the Motorola Amateur Radio Club 
station in
Ft. Lauderdale, Florida (not too far from Carlos' QTH).  Having a 160m
antenna on the roof of an industrial plant, adjacent to regional
high-tension lines, across the street from an electrical substation, in 
a
30-year old suburban neighborhood in the middle of the eighth most 
densely
populated urbanized area of the United States
(http://en.wikipedia.org/wiki/South_Florida_metropolitan_area ) is not 
what
one would call an idea situation, and occasionally we, too, suffered 
from
powerline noise.

Orlando would visit, capture the noise signature using his equipment 
and the
W4MOT antenna, and invariably find the problem in a few hours.  (When 
the
noise was detectable at VHF, he preferred to use the W4MOT 6m antenna 
-- a
4-element STEPPIR with the 6m passive element option, at 26m elevation 
-- to
get a bearing on the noise, since that was the most directional 
arrangement
and the noise was sometimes inaudible with a short whip on the ground
outside the station.)  He would then submit the repair job to the
appropriate FP&L department, which would get to the job in a few weeks. 
 I
would then have the same giddy feeling Carlos is now experiencing -- 
one of
blessed relief:  No More Noise!  No More Noise! Yay!

By capturing the noise waveform at the amateur station, he could 
compare it
to that of a suspect pole when in the field; a match meant that it was 
very
likely that that pole was the source of the problem.

Orlando is by far the best I have ever seen, or have ever heard of 
anyone
else seeing, at tracking down powerline noise, and I am pleased to
acknowledge his work in this forum.

Ed Callaway, N4II
Yes, just one dit away from Carlos...:-)


_______________________________________________
"160-meters is a band for men, not for sissies!" - SM5EDX