[TowerTalk] Noise caused by tower.

[Martin Gary]

Bill, 
I had that same problem with my repeater. I went through the same
proceedure. I put ground straps across the guys. It helped but, didn't
fix it. I racked my brain for some time untill I finally decided to go
up the tower and redo everything. I took all of the connectors apart and
looked for water, or corrosion. Finding everything in good order, I got
someone to key the repeater and watch the limiter meter while I moved
everything around. It turned out to be the one PL259 jumper that was in
the system (I had replaced the rest of them with n type connectors a
long time ago). There is a SO238 connector on my antenna ( a
Phelps-Dodge Station Master) and since I didn't want to take the antenna
apart I didn't replace it. I put an n-type to PL259 adapter in place of
the jumper and that fixed it. Now I can run 250 watts out of the
duplexer with no deflection on the receiver's limiter current meter.

No matter how well you solder the shield of your coax to a PL259
connector, it will eventually get corroded and start making noise.
I have found at least a dozen bad 259 jumpers in the last five years,
and maybe one n type jumper. So whatever you do get rid of as many pl259
connectors in your repeater system as you can!

Send me an email if you have any more questions, unfortunately I've had
to fix lots of those kinds of problems.....

Hope this helps, 
Martin - N3HRT


Bill Fisher - W4AN wrote:
> 
> Our local 2-mtr repeater is having some problems.  We are experiencing
> noise caused by what is believed to be something on the tower when the
> wind blows.  When the wind is "howling", the noise is QRV.  Anything
> short of "howling", and the noise is gone.  Below is a desciption of the
> installation...
> 
> -----------------
> We have an 170 ft tower approximately the size of rohn 65 (no rust).
> The tower is in 20 foot sections and bolted together with 3 bolts per
> section.  The guying is 40 foot apart with 1/4 inch cable on the first set
> of guys and 3/8 inch cable on the top three guys. The guys are attached to
> the tower with guy grips. The tower has only one antenna, a celwave PD 654
> (8 folded dipoles) for a 146.835 + 600 repeater.
> 
> If you shake the guys, the noise will take out a weak signal and it can
> be heard on a medium signal.  A strong wind has the same results.  If you
> turn the transmitter off, the noise is no longer heard in the receiver. We
> strapped the guy grips to the tower and helped the noise problem by 50 to
> 70 percent but its still a  problem at times. The thing I can't
> understand
> 
> ------------------
>

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