Mystery Regulator

[Kevin, VE1TV]

Hello Group!

My Pioneer surround reciever went dead recently and it appears to be a
failure of a regulator in the standby supply. It is marked 78M56A and
identified on the pcb as NJM78M56. it's a TO-220 (mfr is JRC).
I have been unable to locate any data on the web. I expect I could sub it
with something if I knew what voltage it is meant to o/p. (maybe its
variable).
Can anyone help?

Thanks!

 

[Mark D. Zacharias]

Pioneer should have it under that part number. Just to be sure, have the IC
locator number from the board (like IC 206 or similar) and order from
Pioneer at 800-457-2881

It's a fairly standard 5.6 volt regulator. One could just add a diode in the
ground leg of a 7805 regulator and do the same thing.

Mark Z.

 

[Kevin, VE1TV]

Thanks Mark!

 

[Jerry Greenberg]

This should be a 5.6 Volt regulator. You can have it verified by
contacting the parts rep for Pioneer.

Jerry G.
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