26-05-2022, 09:39 AM
(26-05-2022, 07:32 AM)coopzone Wrote: Are you referring to c9 / c11 (trader sheet) trimmers?
And what is the anti modulation capacitor, never heard that term before.
Derek
Yes, C9 & C11. Either occasionally goes short circuit.
Modulation hum from interaction with the mains, normally killed by a capacitor between line and neutral supply after the on/off switch. Now use a type X2 which is designed to fail open circuit.
A bad pin connection on the IF valve UF89 was causing most of the reduced output. I will have to start checking valve voltages to find the other cause/s of the volume being below par.
Boater Sam.
