"David C. Partridge" wrote in message
...
I'd think that any PNP power xistor with an adequate voltage rating would
do - this is just a pass xistor wired as an EF isn't it?

David

I know very little of transistors other than their basic function, so I
don't know the answer to your question above.

As I noted, it's being used to (down)-regulate negative DC voltage. What
might the reason have been to opt for this transistor over a regulator?
There is a +5VDC regulator right next door in the same circuit.

Can I use the regulator in place of the transistor?