If you own an amplifier that uses the metal/ceramic tubes with forced
air cooling you may be in for a surprise. Take a few minutes and pop
the top and see how much dust and dirt has accumulated in the fan and
around the base/inside of the tubes.
I was astounded at the amount that was present in my Alpha 86 and
spent the better part of two hours doing some much needed cleaning. I
feel this information may be useful to others reading this reflector
and if it prevents the early demise of those very expensive finals all
the better.
It is a little tricky cleaning an amp, but cotton-tipped swabs, pipe
cleaners, small artist brushes (long handle), flashlight and, believe
it or not, my Toro leaf blower were used in the process. If you have
a better source of compressed air the leaf blower won't be needed!
Pay special attention to the dirt accumulated on the vanes of the
blower; knock it off with small brush or cotton swab and blow it out.
Also inspect the variable capacitors and clean with pipe cleaner.
It was necessary to carefully remove the tubes and upon inspection
found the air vanes inside the envelop were very dirty as well. A few
shots of a rapid evaporating, non-residue cleaner containing
trichloroethane and propane did the trick. Remember to spray from the
top down and put a sheet of white paper underneath to prove to
yourself just how dirty they were.
After all was reassembled and the amp back on line, there was a very
obvious increase in the airflow felt by hand as well as much quieter
blower noise.
This preventive maintenance will be performed each year now that I
know how dirty they get.
Bill, K4CIA
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|