Stereo amp fuse keeps blowing...why?

Hi, everybody. I'm trying to resurrect a Sanyo component stereo (model JT-350, 80 watts) that was tossed out in the trash. The amplifier has a 125 volt 2.5 amp fuse connected directly to the power on/off switch PCB. It blows the instant you push the switch to "ON".

I don't see any obviously burned-out circuits, capacitors, transistors, or resistors. What would be your guess as to the most likely reason for this?

Thanks very much.

Most likely is S/C rectiifers, or the poweramp S/C - a lesser possibility is the mains transformer.

Disconnect the secondary of the power transformer from the rest, than check the circuitry with an Ohmmeter. If all seems OK (also the fuse does not blow with the transformer secondary floating), return to original (hint: use individual connectors for each of the output circuits of the transformer) and after that, I would use a 50W/110V lightbulb across the fuse holder and try and trace the short. Than gradually increase the wattage of the bulb. You could start with the lightbulbs first and see where the smoke comes out. But then, there is no right way to trouble-shooting, only imagination! E

sanyo Amp JT-350

could this get close for what your looking for?