[Cobaltblue]

Hi Keith

A few questions

Can you read a circuit diagram?

Can you solder ?

Can you interpret Meter reading or own a meter come to that? ( I see you own a Meter)

If the Answer to all 3 is no then you might consider just buying a working P40 its not rare or particualrly sought after.

If you want to have a go and prepared to master those 3 above or indeed can already answer yes.

First thing to do is to get the circuit diagram and have a look at the standing no signal voltages on both channels.

Cheers

Mike T