Marshall VS65R powers on ..No Sound

[g1]

Try comparing the wiper (middle lug) of the mix pot with pin7 of IC7. (constant tone injected at main input jack, nothing in FX loop)

[Begbie]

Try comparing the wiper (middle lug) of the mix pot with pin7 of IC7. (constant tone injected at main input jack, nothing in FX loop)

OK so I get a real nice signal from pin7 of IC7 but nothing from the wiper of the mix pot (VR10)

[Begbie]

Try comparing the wiper (middle lug) of the mix pot with pin7 of IC7. (constant tone injected at main input jack, nothing in FX loop)

OK so I get a real nice signal from pin7 of IC7 but nothing from the wiper of the mix pot (VR10)

[Enzo]

Think about the overall circuit. You have a signal at IC7-7. The signal at the wiper of VR10 is where that signal comes from. SO even though you are not detecting it, it MUST be there for it to come out the IC.

[Begbie]

Going to plead stupidity here. I went to recheck my previous test and was a whole IC out, I was testing IC1 not 7.
There is no signal at IC7-7.
Thanks Enzo for prompting me to double check.

[Begbie]

Have started at the beginning of the circuit and slowly working my way through IC 2 has output but nothing into IC5 so I'm narrowing my search down.

Thanks again for all your help guys.

[Begbie]

Hi
I'm back and hopelessly lost. Im not sure how I should be testing the signal through the Amp. That is should i have the amp set for the clean channel and have all the pots turned down or is that going to give me false negatives?
Also is it worth checking the tubes power supply as suggested earlier? I really want to get to the bottom of this but as I said earlier feel a bit lost, not sure if I'm finding the signal where it should be or more importantly not findiing it where it should be.
IC6 and 7 have no output but not sure if that is due to how the amp (pots/channel) is set up.

[Begbie]

OK so time has been an enemy over the holiday period and I too have been lazier than usual with this thing. I bought another amp but it hasn't got the tone this one has.
I'm going to go back to the beginning and try once again to get this fixed.

I tried plugging the new amp into the line out and fx loop out jacks (separately), they gave the same result, mostly nothing with a sporadic burst of volume that was very dirty.

Like a said I'm going to go back to the beginning and try to nut this out.