[TowerTalk] Re:TH6DXX PROBLEM?

[K8LN - John Schaffner]

Mike, "I Feel Your Pain"!!!  I have a TH7DXX that has similar problems.
Here's the short story.....Great swr, just like the curve in the manual and
some places better.  I noticed that the swr on 15 meters was not the same
from week to week.  Always 15 first then 20.  As long as the weather was
dry, no rain everything was perfect.  The more rain the bigger the problem.
Ten meters would follow only after days of 15/20 being bad.  I always had a
low or dip in swr on 15 but the more rain the lower the frequency would go,
(20.450 mHz) as the wx dried out (it took several days to see a change)
this freq would rise back to the normal curves.   I had several ideas
(replaced the balun right away, no change)  but the answer came from The
Hy-gain booth at Dayton.   I was told that the only way that 10 meters swr
can rise with a rain condition and lower when dry,  is water collecting in
the tip end of the driven element traps. This "was" a problem and "we" at
Hy-Gain corrected it by placing a 1/4 inch hole in the tip end, bottom of
the traps.  My antenna has been up for 13 years and this mod was made after
I was up and running.   He said that over the years that critters have
nested in the traps and clogged the drain hole on the tip end causing the
water to collect in the end of the trap.  The elements naturaly sag allowing
this to happen.  He drew a diagram showing the inside of the trap and showed
me what happens as water builds up in a trap.  It all made sense.  Their
solution is to blow out the traps and drill a 1/4 inch hole in the bottom of
the plastic end caps.   Have I done the fix yet, NO.  I have been working on
getting a local guy here in town to bring out his ladder truck.  Had him
scheduled to do it one week but it fell through.

GL
John


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