peavey cs800s repair...

This old amp came in last week and it's main fault was powering up followed by fast turning fans and one channel led on..

The thing about these amps is, it's a smp amp and uses a very complex power supply circuit lay out.. many years ago I serviced these amps and after checking my notes found the remedy...

So after a strip down and check the o/p's all was well there next straight to the low voltage rail's again all good. time to rethink here as it still was doing the same thing..then on rechecking around the o/p stage it turned out to be the thermal resistors connected within it's main heatsinks these are 1k thermals that aid tracking. these can be brought from peavey spares and after a solder in it was back in working order..

 

These amps can do 1200w in bridge mode at 4 ohms use... there 600w per can at 2 ohms and 420w ish at 8 ohms use...