hifi engine

SONY 2001D Power problem

i had the same problem some time ago, but it disappeared after i opened the unit - looked around, and put it together again.

The symptoms are:

1. Clock display ok.
3. Power on switch, no response
4. Light switch: No light
5. Sleep switch, no response.

AC -> DC power tested, OK.
Batteries: inserted.
Main power switch (lower left side) is ON. (No error msg. when OFF)

I have downloaded the schematic but would appreciate any tips on where to start looking.

Guess a voltemeter would be sufficient to begin with.

I have electronics experience but am quite old now and would appreciate any help i could get.

On the schematic I see the front end of the power circuitry, and it leads to a transistor, Q40, but I'd like to see the "Light switch" on the diagram as I think that might be the first thing to check.

There must be a break somewhere in the power circuit but tracing doesn't look to easy.

It is fifty years since I built receivers and transmitters...