On Apr 19, 3:52*pm, Charon wrote:

The PNP, only the C and E are soldered to anything, the Base is not
connected to anything. Why would this be ?

Just trying to figure out how this works and why only C and E of this
transistor are used ?


I tracked the part down tohttp://www.diodes.com/datasheets/FZT789A.pdf

The transistor is only connected on the E and the C (tab) the other
two are not connected to anything.

Aha! It's a temperature-compensated Zener diode, made by using the
reverse breakdown of the BE junction and the forward CB diode. It
should have about 7 V at breakdown for lowest temperature
coefficient; datasheet suggests you will get 9V or so from this part..

Either that, or there IS some kind of connection to the base, and
it evaporated or is hiding from you...

Purpose-build compensated diodes (like 1N821) are expensive by