John A simpler and more prosaic cause is distortion in the post phase detector amplifier. If this amplifier sees enough of the modulation frequency fundamental component, it could conceivably produce enough second harmonic by itself to produce the observed effect.
Bruce _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
