I use a multi-stage approach:
1. Peak the noise, if possible, with the VHF yagis at my station.
2. Hop on my bicycle with my HT in AM receive mode, switchable between 2 meters
and 432. I find that most power line noise is audible within 4 or 5 poles on 2
meters, 1 or 2 poles on 432. Note that there is some noise from tire static,
but the powerline noise has different characteristics. The bike both gets me
some exercise, and is easy to stop along side the road for further checks.
3. Bring out the 432 yagi, a 5L WA5VJB cheap beam, to connect to the HT to
sweep the suspected poles. (I can carry the yagi on the back of the bike, or
across the handlebars.)
4. Hop in the car, with the W1TRC ultrasonic detector. I don't expect the
utility to send out crews with orders based on my report, but the ultrasonic
does provide a reality check independent of RF re-radiation, etc.
One of my best VHF DX QSOs resulted from this effort. During a lull in a VHF
contest I took out the bike to look for some noise. While listening on 432.100
AM I heard a distorted SSB signal, but identifiable as a VE3 rover calling CQ.
Rushed home (not far away) and caught the guy (75 miles or so across Lake Erie)
on 432 and then moved to 1296 for my second DXCC country on that band :-)
Of course all this may not work so well if the noise shows up only when it
snows :-)
73 - Jim K8MR
-----Original Message-----
From: Charles Plunk <af4o@twc.com>
To: rfi <rfi@contesting.com>
Sent: Wed, Dec 4, 2019 8:44 pm
Subject: Re: [RFI] Safety suggestion to consider when trying to locate new it
is generated by parent company hardware
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
On 12/4/19 7:22 PM, David Eckhardt wrote:
> OK. I confess I've never had a wire fall on me. But there are better
> tools. MFJ (I hate to admit) sells an ultrasonic microphone much like
> those used by professional power providers. It is far better at locating
> problems than the walking battery-powered radio. Arcs and coronal
> discharges produce copious amounts of acoustical energy above our hearing
> frequency limits as well as RF energy. It's a wonderful tool.
>
> Dave - WØLEV
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