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Default What is the fifth transistor likely for?



"Mark Zacharias" wrote in message
eb.com...
"Sjouke Burry" wrote in message
...
mm wrote:
I was junking a moderately priced combo CD, AM/FM/Casette, from 1998,
that I got out of the trash and which wouldn't play CDs anymore, and
it had an array of five output trnasisttors, instead of the usual
four. All are the same size, on one big heat sink. No schematic
of course.

The part numbers are obscured but I can see the ends of several.
1 B1370
2 B1020
3 B1415 (or 01415, or D1415, or ?1415 4 B1020 same as 2
5 same as 3 What is the fifth transistor likely for? Don't put a lot
of work in to this. The device is junked/trashed
already.

Temperature measurement.
Used to keep the bias where it belongs.



Doubtful. As Arfa mentioned, probably a regulator (voltage, not temp).
Quite common to mount on the same heatsink as the output transistors.

Mark Z.


Ha ! Thanks Mark. I was beginning to think that no one had understood
exactly what I said ... :-)

Arfa