DEBUGGING HELP COMPRESSION/DIST.

[diemilchmann]

Ive built this poretty simple compression about 3 times. I didnt bother with the distortion unit, just been building the first part. Its a CA3080 for the OTA, and 2n3904 NPN transistors. Diodes are 1n914. The only change there is is that instead of a.05 uf cap , i used a .047 uf, thought it was close enough. I dont get any sound thought at the output( where it says compressor on). I DO get sound before Q1, and at the - input of the 3080. No signal on the output of the 3080. The schematic is a little MEH in terms of clarity, sorry about the lack of part numbers and such. I have no clue where to start looking. Yes, the pins on everything are right.

Data sheet for CA3080:     http://www.intersil.com/data/fn/fn475.pdf

Schematic: http://imgur.com/VYFVw.jpg

Sorry for the messiness; thank you people!

[oskar]

still voltages would be super nice!   
3080 pin 5 voltage?

[oskar]

On the schematic the negative op-amp input only see a cap. My memory just blanked out completely concerning the ins and outs of the OTA, but I think the inputs needs a DC-path just like any other op-amp. The 1M resistor that passes by (left of the 2k pot) should probably be connected to the - input.         

[PRR]

I agree with Oskar. The schematic is wrong.

[slacker]

Oskar's right, the compressor part is a Dynacomp, if you look at the schematic in the link below you'll see what's wrong.

http://www.tonepad.com/getFileInfo.asp?id=9

[diemilchmann]

Ok, so i connected the 1 M and it seems to be working better today. However, it still makes a really bad crackling noise, fating out when i strum hard. It might just be some weird connections or something, but heres some voltages for SAGs:
batt:9.26v

Q1
C:9.26v
B:8.36v
E:9.2v

Q2
C:9.26v
B:9.09v
E:9.2v

Q3
C:9.2v
B:8.95v
E:9.2v

Q4
C:9.2v
B:8.9v
E:9.21v

Q5
C:9.26v
B:9.15v
E:8.8v

3080
Pin 2:9.04v
Pin 3:9.04v
Pin 5:8.77v
Pin 6:9.09v

Hopefully that helps. And thanks for the schem, it helps.

[oskar]

Check the grounding...

[PRR]

Again I must agree with Oskar: when all your readings are "9V" (pretty much: 8.3V to 9.2V), your "zero Volt" (ground) is probably missing.

[diemilchmann]

Ok, thanks. Youre right>.< theground connection wasnt making very good contact. Everything seems to be working, just need to fiddle. Thanks guys!

[Quackzed]

nailed it!      Nice!

[diemilchmann]

unfortunately, the compression isnt all that noticeable. Like, hardly at all. I checked with the RossDya schem, everything looks fine. Any suggestions on how to boost the compression?