I can relate the same story here. The power company guy came by, I
showed him what direction it was coming from, he went to the nearest
pole with a lightning arrestor in that direction (a little over a
quarter mile away - not every pole has one) disconnected the lightning
arrestor, and the noise went away. He said that was a common failure
mode for those things, he would leave it disconnected, then, just like
Jeff said, he said he would slate it for replacement before next storm
season. That was the last I ever heard of that noise.
Things went from miserable to smiling in about a half hour.
You might have the "noise signature on the shield of your coax" but it
may be possible that if he disconnects the lightning arrestor your
system will revert to its previous satisfactory state without making
changes to your system.
I think what made my experience go well was that I was able to show the
guy the noise, indicate where it was coming from, and confirm that his
action stopped the noise. I was using a portable battery powered VHF
receiver set to AM, plus and a handheld direction finding yagi antenna
to gather my data. Plus a little driving around. I was using 160
meters to show him how useless the noise source made my radio, then how
fabulous it was when he was done. His name and number are now in my
speed dial.
73 - Mark N5OT
On 7/22/2019 10:15 PM, Jeff Blaine wrote:
Around here, lightning arrestors on these power cables are the prime
candidate. I have exactly the same issue here and every couple years
have to go track down one that has started making racket over the
summer storm season. The noise is in-band and you can't filter it
generally speaking. The good news is if your experience is similar to
mine, the power company will be able to fix your noise maker and the
difference is almost literally night and day.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 7/22/19 7:33 PM, Richard (Rick) Karlquist wrote:
On 7/22/2019 3:59 PM, 57JNDenneny@comcast.net wrote:
I am uncertain this will cure problem, My TB and yagi coax shields are
showing a noise signature on his analyzer.
This was a shock as both coax cables have commercial bead type choke
baluns.
Jim K7EG
I'm not shocked.
Bead type choke baluns are rarely effective on 160 meters.
Refer to K9YC's handbook (or read his prolific posts to this
reflector) to learn how to make effective chokes using large
toroids as opposed to beads.
Rick N6RK
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