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mm mm is offline
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Default What is the fifth transistor likely for?

On Tue, 08 Feb 2011 01:23:08 +0100, Sjouke Burry
wrote:

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.


Thanks all. Very interesting ideas. Maybe it wasn't as cheap as I
thought it was. But I had no use for it. I just like to look at
things and fix them when I can.