1Ж42А. As a mixer/Frequency changer????

[Murphyv310]

Just been toying this over in my head. As the diode is positive going I'd expect a more positive voltage on the G1 with a strong signal and the Anode volts to drop, the anode volts on the AF amp is 6.2v after being dropped by the headphones. With the resistor network this voltage is constant irrespective of strong signal or off tune. This test was done with a 10m grid leak and 18m from diode anode to ground. What I will do is wind a 1:1 RF transformer and wire the diode direct to the secondary with the other end grounded.
I've got the feeling the issue is pure and simply the extremely high input impedance and anything will damp it. Even touching the diode reduces volume massively.