I still don't understand what is is doing for you. If you reverse bias the diode the voltage will fly up. There needs to be rf isolation with the choke but a shunt path to absorb the extra bias due to drive.
I'll have to find the circuit somewhere around here or axe the Tron again when I hear him on... it's been many years since I've used it. But it consists of only a diode and power supply choke to stop the rectified voltage from the final grid circuit charging up the bias supply caps to infinity... :-) There IS s a shunt feature to it as I remember.
Seems I also used a relay too, but it is foggy.
T
