Farfisa VIP200 - built in amp help

[A.David.MacKinnon]

I've got a Farfisa VIP200 with the amp built into the stand. It may be my best craigslist find ever, $100 as is with a warning from the seller that it has issues and needed TLC. I go see it and it's perfect. Flawless but not making any sound. When I get it home I discover that the organ itself works fine with no issues but the amp isn't working.
It doesn't appear to powering on. I've checked the cable for continuity between the pins and their destinations inside the amp everything there is good. No broken wires or bad solder joints. There is a small light bulb inside the amp. I assume it's acting as a fuse. It's not lighting up but tested fine for continuity with my multi meter so I'm assuming it's not blown.

Does anybody know where to start with this? Am I missing something really obvious? Are there common problems with these amps I should look for?
I'm also looking for a schematic if anyone has it and wants to share.

I posted this over on Gearslutz as well but christ I hate that place. Don't make me go back there.

Thanks

[dfuruta]

got a picture of the inside?

[A.David.MacKinnon]

Here we go -

[dfuruta]

Easy things to check:
- voltage across the big filter cap with your voltmeter to see if the power supply is working
- bias voltages on the bases of the transistors, to see if something obviously screwy's going on

If you've got a scope it shouldn't be too hard to trace the signal through and see where it stops. Not too many parts involved.

If you get really desperate and can't find a schematic, should be possible to draw one out in half an hour by looking at the traces.

Sorry if this is all obvious!

[A.David.MacKinnon]

Totally obvious but I'm terrible at trouble shooting circuits beyond seeing something that's obviously broken or blown up.
I'm not 100% sure (but fairly certain) that the power is supplied from the organ's built in PS. The organ itself is working just fine so I'm assuming the PS is fine too (I could be quite wrong though).

[dfuruta]

can't hurt to check the power in the amp section! in my (limited) experience the output transistors are the next most frequent thing to go on amps like that, so if you have a way to check the signal right before them that might be the second thing to try

[vvv]

Me, rank amatuer, but I'd track back from that bulb ...

[floid]

The bulb not lighting may be normal, there's a "series bulb" trick for checking amps in which this is the case.
Is the speaker okay? Does the organ work with another amp / amp work with another input?

[A.David.MacKinnon]

I checked the bulb for continuity and it reads ok and looks good (not blown). The organ itself works perfectly with an external amp. The speakers seem fine but the amp itself is 100% DOA. No hiss, hum or sound of any kind.
I'll have to dig into it a little more once I'm home again on monday. Or ship it off to the doctor.

[Snarl 12/8]

I wouldn't assume the bulb is ok from a continuity check. It seems like some current would be traveling through there on normal use, not just a trickle from a tester. It's rare, but I've been thrown off by fuses that checked out normal, but weren't. Hook a low voltage battery up to it and make sure it glows. I'd consider that bulb about as reliable as a moving part in something that old.