Pavey VTM 60 preamp hum

[vintagekiki]

60 posts and no lights at the end of the tunnel.
During all tests, the speaker must be connected to the VTM120.

Check VTM120 to see if it works as a preamplifier.
Connect the preamp send jack J7 to the input any external guitar amp which serve as slave.
If the VTM120 preamp with external guitar amplifier (as slave) has a clear sound (without noise, hum, popping, crackling) then the fault is in the communication between preamp and power amp, or the power amp of the VTM120 is faulty.

Check VTM120 to see if it works as a power amp.
Plug the guitar to return jack J6. If the VTM120 has a clear sound (without noise, hum, popping, crackling) then the fault is in the communication between preamp and power amp.
Carefully inspect communication between preamp BD and control BD.

[wormdirt]

60 posts and no lights at the end of the tunnel.
During all tests, the speaker must be connected to the VTM120.

Check VTM120 to see if it works as a preamplifier.
Connect the preamp send jack J7 to the input any external guitar amp which serve as slave.
If the VTM120 preamp with external guitar amplifier (as slave) has a clear sound (without noise, hum, popping, crackling) then the fault is in the communication between preamp and power amp, or the power amp of the VTM120 is faulty.

Check VTM120 to see if it works as a power amp.
Plug the guitar to return jack J6. If the VTM120 has a clear sound (without noise, hum, popping, crackling) then the fault is in the communication between preamp and power amp.
Carefully inspect communication between preamp BD and control BD.

The guitar amp functions fine that's the funny part. The noise is completely independent of the amp functions I can plug in and play and there is a crackle noise underneath after it warms up it gets quiet enough to easily play over
I have it isolated between the signal leaving v3 and reaching the PI so the next move (without a scope or any method I know of to test) is to start replacing parts

[wormdirt]

60 posts and no lights at the end of the tunnel.
During all tests, the speaker must be connected to the VTM120.

Check VTM120 to see if it works as a preamplifier.
Connect the preamp send jack J7 to the input any external guitar amp which serve as slave.
If the VTM120 preamp with external guitar amplifier (as slave) has a clear sound (without noise, hum, popping, crackling) then the fault is in the communication between preamp and power amp, or the power amp of the VTM120 is faulty.

Check VTM120 to see if it works as a power amp.
Plug the guitar to return jack J6. If the VTM120 has a clear sound (without noise, hum, popping, crackling) then the fault is in the communication between preamp and power amp.
Carefully inspect communication between preamp BD and control BD.

Scratch that I had a small breakthrough
so I used the PV as a preamp for another amp, plugged guitar into the front, sent the signal out from the effects send.. and it didn't "break" the signal from getting to the power amp of the peavey. Essentially I was playing both amps at once. That's strange. I know there is a "booster" jack on it that sends the preamp signal without interrupting the signal to the power amp but I wasn't using that

[The Dude]

The amp input switching is done via the return jack- not the send, so that makes perfect sense.

[vintagekiki]

I know there is a "booster" jack on it that sends the preamp signal ...

It's booster output J7

[SoulFetish]

Wait, have you jumped the effects return yet?
Take a 1/4 jumper cable and go right from send to return and see if that stops the noise.
Have you reflowed and cleaned those effects loop jacks?