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Old September 7th 05, 06:16 AM
Andrew VK3BFA
 
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Andrew Mitz wrote:
Beeswax is exceptionally good for protection from an
ionic environment (salt water, human body).


Rick Karlquist N6RK wrote:

In 1975, I worked for a marine radio company called Konel.
I worked on their first synthesized radio, which I inherited
from another designer. The original design had a VCO that
was quite microphonic. We didn't even bother with beeswax,
we potted itin Red Glyptol. Even that wasn't good enough
for two reasons. The speaker was in the same box and the
sailors would turn it up so you could hear the radio over
the engine noise. Also, the 10,000 HP engines on tug boats
produced a lot of vibration which got into the VCO.
I designed a VCO with an inductor printed on the PC board,
and that did the trick. A few months later, Konel went
out of business and few if any radios were produced.

Rick N6RK


"Larry Gagnon" wrote in message
news
I posted a few days ago about repairing a VHF marine radio.
Thankfully I solved my problem, locating three cold solder joints
in the VCO, which entailed removing metal shields and all the
beeswax that coated all the components. That was character building
work!

I gather the beeswax is to ensure rigid components to maintain
stability of the oscillator? Any other reasons for it? Is it
necessary for me to remelt the old wax and spread it around as
before, or can I get away with just reshielding the VCO?

Any suggestions appreciated.

Larry VE7EA

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Had a Yaesu FT-470R 2m ssb/fm transceiver in recently for repair - VCO
was faulty. The module had been encapsulated in expoxy resin, and took
AGES to chip out with a fine wood chisel (and lots of swearing). Broke
a few components doing it, but could replace them so did. Pig of a job.

I consider this to be the definitive reason why beeswax is a better
potting material for VCO's.

What more do you want? - its cheap, readily available, easy to use,
recyclable, easy to get out for equipment maintenance, smells ok when
melted (better than modern chemicals) - need I say more?

Andrew VK3BFA