"Dan Richardson" wrote in message
...
On Mon, 13 Feb 2006 13:41:24 GMT, "Frank"
wrote:

NEC indicates the coil is 123 uH, and a Q of 4471 at 3.8 MHz. You would
certainly have to silver plate the coil in order to maintain such a Q.
The
formation of copper oxide will cause Q degradation over time -- despite
what
some people seem to think.

It is not just what "some people" think.

Check out: http://k6mhe.com/n7ws/Plating.pdf

73,
Danny, K6MHE

Thanks Danny, Interesting paper. It certainly points out problems with
silver plating. I must say I have never attempted to measure the Qs of
inductors with and without plating, but it is something to think about. My
point was more about the effects of copper oxide on inductor Q. It makes me
think that the best way to prevent the build up of oxide is to use some kind
of low-loss insulating material on the surface of the copper.

73,

Frank