Sanyo M-X920K (no power)

[mark]

I’m about to restart on this after killing it by accident. I was working on the tape deck (everything else worked) while it was plugged in and I shorted it. ️
Anyway it’s completely dead now except the radio dial light comes on, and if I turn the volume up I get this horrible low rumble sound.
I’m thinking it’s a power supply issue.
What should I check first?

 

[Superduper]

If the power supply was the problem, you'd likely see no life. I would suspect the regulators might be blown.

 

[mark]

Well it’s not the power supply. 18V
I’m also getting 16V at the tape deck.
Haven’t found any power at the function switch.

 

[Tinman]

Get a schematic and start tracing and testing.

 

[mark]

If the power supply was the problem, you'd likely see no life. I would suspect the regulators might be

 

[mark]

So this D325 transistor seems wonky
It’s a NPN and when I swap out the leads it’s not showing 0.

 

[Superduper]

So this D325 transistor seems wonky
It’s a NPN and when I swap out the leads it’s not showing 0.

What? ?????

 

[caution]

So this D325 transistor seems wonky
It’s a NPN and when I swap out the leads it’s not showing 0.

Makes sense, that's part of a regulator. Q711 is governed by D718, a 10V zener (the diode in the pic with the green band)