External Power supply is 9VAC for 1.5A. After the diode rectifier bridge the supply goes to 13VDC.
3 tensions are used from this 13VDC power --> 9VDC, 12VDC and 5VDC this last one thru a LM805 egulator.
As a troubleshooting method you can connect a lab power supply tuned on 13VDC directly on the VIN leg of LM805 the regulator + GND, or on the big capacitor following the diode bridge.
If the console is still dead, the problem is elsewhere.