[TowerTalk] Fwd: (80 Meter yagi question) Cu <=> Ag

[Richard (Rick) Karlquist]

On 10/12/2017 5:06 PM, Bob K6UJ wrote:
> Since rf flows on the skin of the tube, I don't understand why silver plated copper
> wouldn't be better than just copper.But what do I know, hihi
> BobK6UJ

A few issues here:

1.  The DC conductivity of ideal silver is only 5% better than ideal 
OFHC copper.  At RF, the conductivity would be only 2.5% better.  That's
the best you could do in an ideal world.

2.  On 80 meters, the thickness of typical silver plating is no where
near several skin depths, so it doesn't help even a few percent,
on account of that.

3.  Copper oxide is supposedly lossy.  Plating with silver gets rid of 
that problem and replaces it with silver "tarnish".  This may be less
lossy.  YMMV.  Aluminum has no issue whatsoever with losses due to
the oxide layer.  It is way cheaper and lighter weight.

Rick N6RK