[Amps] Cool Amp Silver Plating

[Paul Christensen]

However, in the case of Collins ribbon-type roller inductors, coil Q is 
strongly related to the contact resistance of the flat silver-plated ribbon 
against the metallic capstan.  Once a year, I remove the tarnish from the 
ribbons and two years ago, I applied Cool Amp to the ribbons as the plating 
was starting to deteriorate after many decades.  So, here's an application 
where an improvement can be attained with silver plating where the frequency 
of operation is much less than V/UHF.

Photos of the Collins coil pair can be seen on my QRZ.com page.  Scroll down 
to the balanced ATU section.

Paul, W9AC

>> Whether it's worthwhile electrically depends on the frequency. At 144MHz, 
>> the skin depth is 0.2 mil (0.0002 inch) and you need about 5 skin depths 
>> to keep 99% of the current in the silver, or about 1 mil i.e. 0.001 inch. 
>> At 1.8 MHz, you need about 0.009 inches for 5 skin depths....
>>
>> But it looks a lot nicer than oxidised copper.
>>
>> 73
>>
>> Peter G3RZP