Digitech 2101 compressor

[Jmpj50]

Yes it’s got -12v on pin 4. I checked R122 I can’t remember I’ll check it again tomorrow Let u know. Thanks for the help

[g1]

Yes it’s got -12v on pin 4. I checked R122 I can’t remember I’ll check it again tomorrow

Also please re-check whether the voltage on U62 pin6 is positive or negative.

[Jmpj50]

Ok pin 6 of u62 is +11.16v and r121 has + 12.24v coming in and r122 has - 11.90. When I try to adjust p2 it’s just stays at + 9.55v.

[Jmpj50]

To me something ain’t right with u62 in that part of the circuit. It’s putting 9v out at pin 7 and that’s going up to u9a.

[g1]

U62, pin5 is grounded. You verified it was 0V. Pin5 is the + input, pin6 is the - (inverting).
If you have 0V at pin5, and a + voltage at pin6, the output should go negative (because non-inverting input is more negative than the inverting input).
So U62 seems to be bad. If you want to check before you replace it, lift one end of R119. You should now be able to get 0V out of the trim pot.

[Jmpj50]

Ok I’ll check

[Jmpj50]

Ok I cut one end of the r119 that worked I adjusted p2 down to 1.4mv on pin 1 of u9 yay. So I will have to change u62 right. I will have to look and see if I have a lf353 if not I will have to order1. Hopefully this will fix the compressor. I’ll get back to you later next week tell you if that fixed it. Thanks again for all the help.

[Jmpj50]

Ok I did find a lf353 and I kinda rigged it I cut the pins off the old one left them soldered to the board. And soldered the new 353 to them just to see if the compressor would work. Guess what it works now. I will have to pull the whole pcb board out this weekend it’s kinda a pain we’re I can solder the 353 in. The only thing when I adjust p2 it will only go down to about 1v that’s for it will go. I still got some more tweaking to do. But it works. I really appreciate all the help you did can’t thank you enough.