"klem kedidelhopper" wrote in message
...
I'm working on an old Bogen CHS60 60 watt PA amplifier. This is a
direct coupled amplifier and almost every transistor is blown. A real
mess. Except for one small signal transistor,, a 2SA539Y all the
other TO92 types are 2SC945L. In addition there are two TO220 drivers
and two TO3 outputs. I have been replacing the 945 TO92's with 2SC1815
types which is what I have in stock. Both types seem to cross to an
NTE 85 so I figured this would be a safe bet. However I just noticed a
problem. The problem is the two remaining good 2SC945L's on the board
seem to test OK out of circuit however the base is definitely in the
center on both off them. The board is marked EBC for all of these
types as well but the spec sheets for both the 945 and the 1815 types
shows that they are ECB.. The interesting thing here is that the spec
sheet for the 539Y shows EBC as it is marked on the board. I have
never seen where two transistors bearing the same number were
configured differently but is this possible? It certainly seems that I
have installed all these 1815's incorrectly. Does anyone have any
further insight on this? Really confused. Thanks, Lenny



I came across a similar problem years ago when spending hours trying to
repair a C-Audio power amp.
Turned out the BC184 and the BC184L have different pinouts.
AAARRGGGHH!

http://www.datasheetcatalog.org/data...s/mXyztqtw.pdf



Gareth.