[Amps] Crackling noise, SB-220 repair notes

[Tom W8JI]

>i got this with a drake L7 some years ago.The couldprit 
>whas a broken diode
> in the ps.
> amp wkd ok ,later on it before fixing it started also to 
> smell !
> on4ma

I'd go along with that...or perhaps a bad capacitor or a bad 
equalizing resistor across a filter capacitor.

As a matter of fact I'd carefully check all the equalizing/ 
bleeder resistors. Electrolytic capacitors often make a soft 
click or thump when arcing internally, and the most common 
cause is an open equalizer.

73 Tom