[TowerTalk] R-7000 Problem

ValErwin@aol.com ValErwin@aol.com
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!   

Good Luck

Val L. Erwin

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