> From: Fraser Robertson <f.g.robertson@open.ac.uk>
To: <amps@contesting.com>
> Date: Wed, 3 Sep 97 09:27:01 +0000
> Hi all, can anyone explain to me why silver plating is used to
> decrease loses in tank circuits and so on.
Two reasons I know of Fraser.
1.) People mistakenly "think" it helps Q at HF and lower VHF.
2.) The plating makes the tank look pretty.
> Looking at the figures
> there seems to be a very small difference in resistivity and skin
> depth between silver and copper. Is is to reduce losses due to
> tarnishing perhaps?
Perhaps, but a nice coating of a cheap good clear dielectric would be
just as effective.
Three identical # 8 AWG mobile loading coils I measured had a Q of
387 UN-plated, 384 tinned, and 389 silver plated. A large edge
wound silver plated coil had a Q of just over 400.
Hardly any real world difference!
73, Tom W8JI
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