[R-390] R-390 RF Gain Control

[Jacques Fortin]

Charles,
With all due respect, I do not agree that anything made in the far east and sold on Amaz... can be up to the task.
The RF gain control, and especially in a R-390, have to handle the cathode current of many RF + IF stages and this is why a 2W rating part was originally specified.
The El Cheapo variety that can be found on the web sites is usually rated for 500mW, then in theory unfit for the purpose, or not expected to last very long. 
The parts distributors, like DigiKey, are actually listing the right replacement part (see attached).
But they have none in stock.
A couple of years ago, I went as far as contacting the manufacturer (PEC = Precision Electronics Components) directly, just to get the answer that the MOQ (Minimum Orderable Quantity) was 1000 pieces.
And that the price was around $25 USD EACH.
Ha... If there is 1000 owners of R-390 or R-390A that are willing to invest ~25 USD in that project, I can handle it.
Otherwise....
The only remaining alternative is to order "cannibalised" parts from Fair Radio, but they can be worn already when you receive those.
Meaning, I do not believe that they are tested for anything before they are shipped to you.
I believe you can figure how I know...

73, Jacques, VE2JFE
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