Sisu MT
Well-known member
Greetings good people at GroupDIY. Getting a 100hz hum off the repro head when recording (electrical hum). It's on channels 17-24, so I tried swapping audio power supplies and that made it clear the issue is with the third audio power supply. All the elcaps and rifas have been updated previously, so wondering if it might be a bad rectifier. Have a scope, but not sure what I should measure to trace the issue. Any guidance is greatly appreciated.