[Collins] 30L-1 TUNED INPUT PROBLEM

[Dr. Gerald N. Johnson, electrical engineer]

Yes, 30s vintage tubes (and 811a ARE 30s vintage tubes) have enough lead
inductance that their gain goes down above 18 or 20 MHz, and their input
impedance changes. Yes they work through 6m, but not at full power. Lead
lengths that are negligible at 3.5 MHz are quite significant at 28 MHz.

73, Jerry, K0CQ, Technical Advisor to the CRA.
-- 
Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
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