20-01-2018, 04:29 PM
(This post was last modified: 20-01-2018, 04:30 PM by peter scott.)
Hum in your 40/41 could be caused by various things. A common problem is circuitry drawing too much current from the power supply and a possible cause is leaky capacitors.
You could try disconnecting C3,C4,C9,C10,C13 or C20 just to see if the hum disappears.
The smoothing capacitors on the output of the power supply are also possible suspects. C24 and the other one without a number.
Peter
You could try disconnecting C3,C4,C9,C10,C13 or C20 just to see if the hum disappears.
The smoothing capacitors on the output of the power supply are also possible suspects. C24 and the other one without a number.
Peter
