Carlsbro Keyboard 150 , 15 inch combo from 1985
 

TO220 devices marked 40871 and 40872 and also SM are presumable RCA40871 /2
, anyone happen to know what the TO3 devices are , presumably NPN and PNP,
cold test seem ok. Usual Carlsbro, locked behind rivetted heatsink,
otherwise prea looks like HH Marlin type amps

Carlsbro Keyboard 150 , 15 inch combo from 1985
 

I should know the identity of the TO3 tomorrow , both NPN on rechecking.
Loose Collector bolts so I have to get to the other side to tighten. Not
rivets , looked superficially like aluminium rivets . On Googling ,maybe cct
similar to this admirable effort at unravelling to a schematic, the Stingray
amp

http://ax84.com/bbs/dm.php?thread=467875

Carlsbro Keyboard 150 , 15 inch combo from 1985
 

Even more like the Stingray. 2x MJ802 , 1 BC182 and 3xBC557 instead of 3x
bc212.
Soft blown (not blacjened) ps fuses and mains fuse , then abandoned for 10
years, no recollection of original failure scenario and nothing found, cold
so far , a likely culprit