Oh, a tip if you do use a portable AM broadcast radio. Wrap some
aluminum foil around the radio. Then you can slide that up or down the
radio to use as an attenuator to tell when you get close to the right
pole. But I have found that tricky at best when in a old neighborhood
like mine where maybe many poles are emitting some rfi at AM broadcast
but may not be bothering ham bands. A better solution is a portable
communications receiver with AM mode and some VHF yagis at various
frequencies. Power line rfi diminishes with increased frequency thus you
can use that to your advantage to narrow it down to the right pole. Keep
in mind also the blame arc can use the lines as an antenna to throw you
off further. Its an art to where I am still a novice. I pay attention to
every word Mike Martin says.
-------- Forwarded Message --------
Subject: Re: [RFI] Safety suggestion to consider when trying to locate
new it is generated by parent company hardware
Date: Wed, 4 Dec 2019 19:44:26 -0600
From: Charles Plunk <af4o@twc.com>
To: rfi@contesting.com
Years ago, I built the ultrasonic from the QST article
(http://www.farcircuits.net/w1rtc_notes1.pdf). Works good unless the
source is masked by the hardware. I have found it is very pinpoint in
nature. You have to find the pole by df'ing then use the ultrasonic to
scan the pole for individual hardware. I df with either an FT60 or FT817
on AM and various hombrew yagi's. Of course AM broadcast in the SUV for
very broad location. My current source pulsed at first, very
distinctive, and I could pick it up almost a mile radius on car AM
radio! One source, years ago, I could hear it with the ultrasonic and
took a photo of the individual hardware & pole number. Then emailed it
to my contact at the utility. That was neat.
My current source, I have been unable to hear it with the ultrasonic.
Since the pole I suspect by df is scheduled for replacement anyway, have
hung up my tools until then.
Chuck
AF4O
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