polaris26 Messages: 6 Registered: December 2017 Location: PA, USA
Junior Member
Just a quick update as I had some time this evening to do a little work on the ol' Kustom -
I took the PA/voltage reg board (PC703) out of the amp and started checking some things in and out of circuit.
I found two 6.8uF 35V Tantalum caps were dead shorted (< 1 ohm). These are the ones tied to the output rail and running to opposite ends of the bias diode string. The rest of the caps tested ok, but I decided to replace most of the ones in the audio circuit anyway. I checked the transistors and diodes, and none appeared to be malfunctioning, so I am guessing the shorted caps were responsible for the high DC offset in this case.