Guyatone Flip MKII GA-2000 Amp - screen resistor values?

[Jazz P Bass]

We do not have a schematic, do we?
Do ANY of the controls affect the noise?
If so, the problem is before that control.

[beedoola]

We do not have a schematic, do we?
Do ANY of the controls affect the noise?
If so, the problem is before that control.

I posted the schematic in post #9

The treble pot makes noise when I touch it, like ground hum but it doesn't affect/lessen the general noise...

[Jazz P Bass]

Yeah, the treble pot connects through a coupling cap to the FET.
That will make it hum.
How old is the amp?
Those FET's may be the noise source.
Then again I see an awful lot of electrolytic bypass caps.
It's hard to tell if they are leaking, short of replacing them or tacking on a temporary cap in parallel.

[beedoola]

Yeah, the treble pot connects through a coupling cap to the FET.
That will make it hum.
How old is the amp?
Those FET's may be the noise source.
Then again I see an awful lot of electrolytic bypass caps.
It's hard to tell if they are leaking, short of replacing them or tacking on a temporary cap in parallel.

I think the amp is from the early 80s, maybe late 70s.

You're talking about VR2 - thats the treble pot right?

[Jazz P Bass]

Yup.
VR2 is the Treble pot.
Do you have access to a scope?

[beedoola]

Yup.
VR2 is the Treble pot.
Do you have access to a scope?

unfortunately I don't

[beedoola]

now it seems some ground noise is there regardless of whether the master volume is on or off..

IMG_2977_zps7aef5d6e.mp4 video by Beedoola | Photobucket

[beedoola]

I still haven't figured the issue out. I was poking around and found this wire coming from the ETO transformer that had been cut and taped. Whats this line not used or might it been clipped for whatever reason?

The Blue/Black/White wires are coming from the other side of the transformer.