[AMPS] Silver plating

Wed, 3 Sep 1997 09:13:47 +0000

> From:          Fraser Robertson <f.g.robertson@open.ac.uk>
> 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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