"Sam Goldwasser" wrote in message
...
| "NSM" writes:

| If you find. say, 12.3 VDC across the terminals (assuming the old diode
is
| open circuit) then I'd try 10 VDC. As for power I would eyeball it.
|
| Why?
|
| If I find 12.3 VDC across a zener, I expect it to be approximatley a
| 12 V zener.

I'm assuming the zener is open (OP says burned out). I'd also look for other
clues to voltage - cap rating, chip rating etc. This would be easier to fix
if he had another working unit!

N