Mauri 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").
>I can report a brand new (bright, shining) copper VHF cavity,
>part of a duplexer, had a certain bandwidth and attenuation.
>The same cavity was then silver plated. The bandwidth
>decreased toghether the attenuation.
>
>The same was done in a similar cavity but UHF, the difference
>was markedly bigger.
OK, I'll cheerfully revise my opinions when presented with good evidence
- there's no shame in that.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.demon.co.uk/g3sek
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