I'm trying to fix a 70's channel strip, it has BC107B transistors in it. I think one of them is no good; I get 20v on the Collector, and 0v on both Emitter and Base. Anyhoo, apparently they're kind of hard to come by? Can anyone suggest a suitable replacement?
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=497-6654-ND (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=497-6654-ND)
http://www.newark.com/jsp/search/productdetail.jsp?SKU=89K0461&CMP=AFC-GB100000001 (http://www.newark.com/jsp/search/productdetail.jsp?SKU=89K0461&CMP=AFC-GB100000001)
http://www.mouser.com/ProductDetail/STMicroelectronics/BC107B/?qs=sGAEpiMZZMvAvBNgSS9LqjWGChRnAueE (http://www.mouser.com/ProductDetail/STMicroelectronics/BC107B/?qs=sGAEpiMZZMvAvBNgSS9LqjWGChRnAueE)
Not sure on a sub... maybe the MPSAxx? I looked at the BC108, it's voltage rating isn't up to par. 5088/89 is about the same max values as the 108.
Hi
BC107B was state-of-the art in the day.
It is probably there because it was low noise and high hFE. 2N3904 is the same concept, improved. 2N5089 and MPSA18 similarly.
For a device with similar characteristics (ie unimproved) you could use a BD139 (different pinout).
cheers
I have some used ones here that came out of an old solid state Hammond. I have used them in some fuzz pedals. PM me and I'll send you some...
MPSA06 might work (just a guess).