[TowerTalk] R-7000 Problem
Thu, 14 Oct 1999 18:40:53 EDT
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!
Val L. Erwin
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