Ian White, G3SEK wrote:
>>I've more than some doubt if available copper is really a
>>better conductor than silver plating.
>>
>>Under my eyes, a big power commercial VHF/FM amplifier
>>prototype was on test and the tuned line, a bare copper
>>machined from a single piece, heated quite a lot. The same
>>line, after silver plating, didn't develop any abnormal heating.
>>
>QRO is a good test - any losses are easy to notice. It seems like the
>available silver plating really was better than the available copper
>(and probably neither was "textbook pure").
Unfortunately, I don't have all of the messages to this thread on my
machine here at home, so I'll probably have to post a follow up from work
tomorrow morning.
Anyhow, silver is a FAR, FAR better conductor than copper. A cavity that
is silver plated will have much better Q and far less loss than an
equivalent copper cavity.
One of the items I sell are cavity resonant filters for the cellular
bands. Guess what - they are all silver plated.
Perhaps someone has said all this before and if so, I apologize. But if
you can get a good silver plating on an amplifier cavity that is
outstanding. You'll have better performance than plain ole copper. One
possibly "cheap" way to do this is by using silver paint. Silver paint
itself is fairly expensive but it may be cheaper to coat a cavity that
way than by sending it somewhere to get electroplated. I am not sure how
good the silver paint would work, but I know it is conductive. We used
to use it in microwave radios all the time.
Anyhow, I'll read more of the thread and make further comments tomorrow.
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
"A life lived in fear is a life half lived."
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