Electro Harmonix Bass Balls

[Rich Guastella]

I have the original...about 30 something years old just found it again..,(in the garage under allota stuff..)..and I was so happy!!!...any way i doesen't work...the battery got real hot so that gives me a clue as to whats wrong,,,,,any Ideas out there!!???
Rich

 

[TheMutt]

Have you tried a different battery, or cleaning off the board with contact cleaner? Might also check the traces to see if anything is severed or any solder joints cracked.

 

[Ba55Man1ac]

Hey Rich.

The battery getting hot indicates a lot of current flowing. There's something gone short (or very low resistance) inside. I'll put a dollar on it being a shorted polarity protection diode. Are you handy with a multimeter?

 

[mikeboth]

I'll put a dollar on it being a shorted polarity protection diode.

I doubt EH used such 'expensive' and 'advanced' protection technology 30 years ago, as it would mean spending another cent or so on parts, plus extra assembly time.

Anyway, the schematic from '78 doesn't show such a diode, but it does show some elctro caps. These should be replaced before anything else is done - it might even solve the shorting problem.