Hi Jerry,
Dunno about Matt Dillon (Kevin's) situation, of course. I had a 70 foot
Rohn 25G tower guyed at two levels. Lowest was 30 feet, highest at 60 feet.
Guy wires were galvanized steel but terminated in contraptions I got from
the local power company. They compressed the cable and had stainless loops
which would just fit around a tower leg. At the lower level, the loops went
directly around the three legs. At the higher level, I had fabricated three
sections of square, steel stock clamped to the tower legs with U-bolts and
with eye-bolts at the free ends. Each of these sections was about
three-feet long. The aforementioned stainless loops went through these
eye-bolts.
When I had pretty much determined that they might be the culprits, I went up
the tower and "wiggled" all those loops to wear away the corrosion. This
worked swimmingly well to completely eliminate the interference on 40
meters. I went back up the tower and clamped copper braid from each guy
wire to the tower itself. That served for years thereafter to prevent the
interference altogether.
I never noticed interference on bands other than 40 meters.
73, Mike -N4NT-
----- Original Message -----
From: "Dr. Gerald N. Johnson" <geraldj@weather.net>
To: <tentec@contesting.com>
Sent: Thursday, October 07, 2010 1:57 PM
Subject: Re: [TenTec] Century 21 Analog Question...
> Certainly a possibility.
>
> 73, Jerry, K0CQ
>
> On 10/7/2010 11:47 AM, Mike Hyder -N4NT- wrote:
>> I had a very similar thing on rigs in my shack. The trouble in my case
>> was
>> that the mechanical connections of my guy wires to my tower were not
>> bonded.
>> Apparently the oxidation in the joints served to create harmonics and
>> thus
>> third and fifth order intermod products of two or more local AM broadcast
>> stations. Probably not your trouble, but might give you an avenue to
>> follow.
>>
>> 73, Mike Hyder -N4NT-
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