I rebuilt an XA last summer. It had only been up 2-3 years, so I was
not expecting to have to replace the capacitor caps. But when I got it
down, I found several were cracked.
Here's an excerpt from a previous post containing relevant info:
Initial visual inspection showed 7 out of 40 of the blue capacitor caps
were cracked. I also did DC resistance measurements of the traps and
found that most traps had a total series resistance of 30-50 mOhms
(milliohms). Two of the traps had resistances of 200-300 mOhms. I traced
the high resistance to the large end of the most outboard shorting
strap (15 meter section).
I called KLM and spoke to Bruce about the caps. He said they should have
lasted 10 years in normal UV exposure, and that there were only 3 explanations
for their premature failure. These were (1) installation with a hammer;
(2) installation using oils as lubricant; or (3) bad lot of plastic.
I told him I hadn't used (1) or (2), and he very kindly sent me a replacement
set for NO CHARGE, to replace the set I had bought for the prior rebuild.
I'd call that great service from an antenna maker!
I rebuilt the antenna using the new caps. Bruce told me that the best way
to install the caps was to warm them up in hot water. This is a great tip!
They went on really easily once they were warm.
Hope this helps...
-Tony, K1KP, firstname.lastname@example.org
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Administrative requests: towertalk-REQUEST@contesting.com