Carlsbro Keyboard 150 , 15 inch combo from 1985

Mar 07, 2013 2 Replies

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


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

formatting link

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

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required