Need help with a Crate G120CXL

[russell072009]

Hello,

I rebuilt an old crate amp a while ago. I know it's not a high end amp but it was something fun to do. I replaced all the electronics with higher quality parts and it, for the most part, works very well. The issue I have is with the chorus circuit. The amp has almost no noise unless you switch on the chorus. then I get a lot of static that changes with the rate control for the chorus. I tried hooking up an oscilloscope to it today and quickly realized it's been far too long since i've used one to troubleshoot a circuit. I tried connecting to the input for the chorus circuit and the output to compare the signal and the readings i was getting made no sense to me. There are also 2 pots on the board that i would like to adjust but i'm not sure how to. One is bias and the other is for the chorus level i believe. Can anyone help me troubleshoot this issue? Point me in the direction to figure out what in the chorus circuit is making the noise? Any help would be appreciated.

Here is the schematic
G120C & CXL Schematic.pdf

[The Dude]

The schematic link is dead for me.

[russell072009]

Ok. I don't know why that is not working. Try this.

https://www.dropbox.com/s/hfhow39bkq...matic.pdf?dl=0

https://www.dropbox.com/s/hfhow39bkq...matic.pdf?dl=0

[g1]

Here's a working copy of schematic: