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Old April 18th 04, 04:32 AM
Richard Clark
 
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On Sat, 17 Apr 2004 21:45:46 -0400, "JLB"
wrote:
What about silver plated RF connectors?

As far as that goes, there are also plenty of gold plated connectors out
there.


Hi Jim,

What about them indeed? If they don't meet the requirements of bright
untarnished metal, then they need pressure mating (all the good ones I
know specify this - but deeply embedded within their core
manufacturing specs) e.g. Amp RF connectors:
"Insufficient contact force will give rise to metal to oxide
junctions. The classic rectifiers were metal oxide by
composition.

"The applied mounting force is concentrated in the surface area of
the protrusion which, on engagement with the panel, punctures the
existing oxide layer to give a metal-to-metal, gas-tight
junction."

The gold plating, presumably, precludes giving rise to oxidation
products; however, pressure then becomes an issue of mating surface
area (Ohms). Every precision contact used for Resistance and Voltage
standards (in the old days) were tapered brass plugs that could be
wedged into the jack with a twist (pressure). They knew about gold
then too, but brass served admirably.

73's
Richard Clark, KB7QHC