Mike Further to my previous message, my full-bridge PA uses 500 volt FETs (STW20NB50) and runs with a supply of 80 volts on load, 100V off load, so you may want to use a slightly lower voltage varist
I tend to agree with Rye and David. I'm not at all familiar with the Decca gear, but a varistor directly across a transistor is a protection technique I've seen used elsewhere in RF amplifiers. Its i
A component across one of the transistors burnt out. I have a diagram but do not recognise the symbol (perhaps a temperature variable resistor?). It is called R31V and the symbol looks like a preset
