I have a Sony SLV-E700 and it has the same problem. It would not power up after someone unpluged it. I have power in the primary power supply up to the pins 1 2 3 4 on the SR526 switching board after that it is dead. There are no voltage readouts at 6 (13 v) and 9 (6v). Pins 7 and 8 are GND. The board No is: SR526 NE M PF2 Mitsumi Elec.co.,ltd 68-4369c Could you please let me know where I could purchase this board? I am a service engineer living in UK. thanks in advance

What is the model # and brand.
More than likely what has happened is about a half a dozen capacitors in the pwer supply need replaced. The caps dry out and work fine until power outage.