Quad 306

[Zombie]

Hello!
Added 7912 and 7812 reg to the emitters of the pass transistor, used a 15V zener instead of 12V (to regulate 15V to 12V).

Seems at least one reg fried, the transistor got really hot after that, so I ended the test.
Seems it the reg couldn't take the initial voltage at startup, or?

I put back the 12V zener, removed the regs, and everything fine again...what could have gone wrong?
Cheers,
Tom

 

[LesW]

Check the manufacturers specs of the regulators, you'll find that 50 volts is much too high as an input voltage.

 

[Zombie]

Hello!
Well, the pass transistor was supposed to take care of that but smth went wrong...
tom