Original poster: "Qndre Qndre" <qndre_encrypt@xxxxxxxxxxx> I was able to find more information on quench gaps. Have a look at the quote.
As to the gaps you are describing, they are called "quench" gaps. The metal discs are separated by gaskets of mica. The mica gasket determines the gap distance between plates. The gasket prevents air exchange, so as the gap breaks in, the O2 is consumed and they run with in a nitrogen atmosphere.
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The advantage of the quench gap is they produce a continuous wave (undamped) oscillation in the tank circuit.
(Originally released by Richard Quick, 10-05-1993) Regards, Q.