HI, I am looking for a circuit diagram for a 1988 CUSTOM SOUND CUB 60 LEAD/CHORUS amp. My friend next door has had a look at it, and the power section works, and he's tried changing a couple of the early stage chips, but he says he can't go any further without a circuit diagram. It would be nice to get it going again.I had exactly the same amp in the mid 80's i bought new and within a few weeks had to take it back to the factory in Leeds to be repaired with the same fault eg power leds come one but no sound just speaker hum, any help would be appreciated. Cheers