I had similar problem. Prior to Dayton this year, antenna gradually failed,
but auto-tuner in IC-756 disguised the problem from me. Prior to Dayton
only 10M was working. At Dayton I spoke to CC rep who was fairly certain
CT1 had failed. In all honesty, I failed to write down which trap had
failed so am not 100% certain which trap he said failed. But it was
definatly a trap failure which the rep had suspected. After Dayton 10M had
also failed but eventually came back to life. Due to other priorities and
guy ropes from another mast in the way, I just got around to taking antenna
down Sunday night.
Some bugs and debris were in box at base. Cable ties have snapped that hold
the inductors. It looks like it may be a pain to replace the cable ties.
I'm wondering if an alternate method can be devised to hold the inductors in
place.
I had hoped to take a look inside the traps, but I see the dimples in tubing
that holds them in place. I think I may be better off not taking a look
inside.
The vice method of removing rubber seal worked!
The traps are getting loose. The most severe looseness is at base of CT1.
It looks like I can rework all three traps as ValErwin has suggested.
Hopefully, my results are as good as his.
Comments?
7 3
Bob
-----Original Message-----
From: ValErwin@aol.com <ValErwin@aol.com>
To: aa4lr@radio.org <aa4lr@radio.org>; towertalk@contesting.com
<towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Thursday, October 14, 1999 7:31 PM
Subject: [TowerTalk] R-7000 Problem
>
>Bill:
>
>I also have a R7000 that I use as a backup to my CC X7. Dunno' what kind of
>problem you are having with your R7000. But, I have also had problems with
my
>R7000 that I will refer to as the "swaying SWR" problem. The problem
>manifested itself as follows: Whenever the Texas wind blew such that the
>R7000 was actually swaying, the SWR would go from 1.2:1 to 7:1 or higher!
>This problem was evident on all bands except 10M.
>
>A call to CC yielded a "duh" and "Gee, we never heard of that one before."
>
>Knowing that the traps on the R7000 are in quasi-series circuit, that
>pretty well eliminated the problem to somewhere in the BOTTOM trap
(10/12M).
>Yep! Once I took down the R7000, I found that both the top and bottom
screws
>that secure the two inner trap windings to the top and the bottom of the
>aluminum trap-tube were loose. In fact, I could see evidence of arcing
where
>the wire (inductor end) is secured to the outer trap surface. I removed
both
>screws (top/bottom) wire brushed the trap-tube and wire ends and resecured
to
>the trap body.
>
>NOTE: When you rework the traps, I found that it was very easy to remove
the
>top rubber-type weather seal by placing the trap in a vise that was open
>slightly wider than the aluminum portion of the trap. Then, draw the trap
>through the vise letting the vise jaws remove the rubber-type weather seal.
>Caution: When you replace the coil end screws don't over torque because you
>are going into a nylon type material.
>
>Out of curiosity, I also checked the other traps. I found that all the
wire
>trap ends had worked their way loose but nothing approaching that of the
>bottom trap. I gave all the traps the same "treatment".
>
>To make a long story even longer, when I got finished, the SWR of my R7000
>was better than it had ever been!
>
>Good Luck
>
>
>Val L. Erwin
>W5PUT
>
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>
>
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