[R-390] Improving Lee Prod Det and SSB AGC mods

Jacques Fortin jacques.f at videotron.ca
Mon Aug 28 12:26:44 EDT 2023


Hello Larry, 

That's funny: I figured the same some months ago, but never found the time to try it !
Let us know your latest AGC implementation related.

Another "mod" I developed for the R-390As is an AGC derived SQUELCH function.
The original implementation of the SQUELCH function used the voltage from the AM detector to work, but the whole circuit was not useable for SSB with the W3JHR mod. and variants.
My SQUELCH trigger uses a 6AK5/5654 and a small Zener which the value depends on the relay coil value used for the muting in the plate circuit.
Yes, I know, complete heresy, but it was the only way to achieve a 1 volt hysteresis gap from the AGC line...

73, Jacques, VE2JFE in Montreal



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