Ampeg SBT power amp

[70spbase]

and the other end of the fuse holder goes where?

To the orange twist cap along with the power switch lead and the black lead from the power cable. The other end of the switch goes to the post terminal

[Hangman]

here is a picture of the power cable wiring from the schematic. I've labeled the white and black wires.

the black wire from the power cable will come in, go to the switch, then the fuse, then one of the wires coming from the power transformer.

the white wire will come in and go directly to the power transformer.

the power light will connect to each side of the power transformer, ie the white wire from the power cable, and the wire from the fuse.

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be vary careful with this. do you have a variac? you don't want to accidentally short the black and white wires from the power cable.

[70spbase]

here is a picture of the power cable wiring from the schematic. I've labeled the white and black wires.

the black wire from the power cable will come in, go to the switch, then the fuse, then one of the wires coming from the power transformer.

the white wire will come in and go directly to the power transformer.

the power light will connect to each side of the power transformer, ie the white wire from the power cable, and the wire from the fuse.

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be vary careful with this. do you have a variac? you don't want to accidentally short the black and white wires from the power cable.

Thanks a lot!

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Thank you, I don't see which one is white or black on your schematic though. I get it though. Really appreciate you time. I'll keep you posted if that is ok.

[Hangman]

hmm, strange. I annotated the pdf and when I click on the attachment on my last message it comes up with the text labeling each wire.

hopefully my explanation was clear. be safe.

[70spbase]

Ok I will check it on the computer when I get home. Maybe because I am on the mobile it doesn't show up.

[70spbase]

Just saw where you marked black and white. Thanks again.

[70spbase]

Hello, sorry to bother again. I wired it exactly as you specified in the schematic. The light is on! Also on firing it up it did hum for a second, then a little bit of smoke from a capacitor on the board that feeds the speaker connection. It is on, yet I am not getting any audio.

[70spbase]

It seems that is why the previous made his mods.

[Hangman]

yes, it sounds like you've got some power amp problems.
though I think it is just as likely that the previous owner made the mod, and used it as just a cabinet. which caused the power amp failure. hard to say.
if you are not familiar with repairing solid state amplifiers, it might be best to let someone else take it on.

its just as likely that you will have to replace resistors and capacitors as it is transistors. hard to say which ones without testing.

do you have a multimeter?

[70spbase]

yes, it sounds like you've got some power amp problems.
though I think it is just as likely that the previous owner made the mod, and used it as just a cabinet. which caused the power amp failure. hard to say.
if you are not familiar with repairing solid state amplifiers, it might be best to let someone else take it on.

its just as likely that you will have to replace resistors and capacitors as it is transistors. hard to say which ones without testing.

do you have a multimeter?

Yes agreed. I have a bit of wiring experience, but not to your level I'm sure. I do have a multimeter and I have been checking some of the resistors and the caps. There are 47 on the main board and most of them do give a reading, yet I think I may need a different meter. As mine is a Radio Shack mini digital and it doesn't seem to give accurate readings.