Anyone who has built PRO CO RAT

[R@bbiT]

Finally I have finished the work on ProCo RAT distortion. I tested it and got shoched when it didn't work, but then I realized that it is working but the signal is very very very quiet (a bit louder than background noise). So I don't know wat is wrong I checked everything- everything is right. Maybe there is some half-dead parts or what ever I don't know. I need some advice because no-one could help me. My only hope is YOU.

PLZ help I am starting to cry (these kind of problem appeared for the first time)

Thanks

[Sic]

check all ground connections and anything that is polarized... (caps, ic pinouts etc etc) make sure all negative and all positive are the correct side if so required...

also, did you test your battery with your dmm ?

[petemoore]

IC pin voltages help debug, take some readings and analyze them, or post them here. Take notes on V readings from pins 1-8 / and ground.

[AL]

Build RG's audio probe. It'll take 10 minutes to build and save you HOURS of debugging.

http://www.geofex.com/FX_images/audioprb.gif

AL

[Mark Hammer]

Step 1: Verify that the pinout for the FET you used corresponds to what you *thought* it was.

[Michael Allen]

I had the same problem. The FET was reversed. Try that first.

[OscarMeat]

I know this is old topic but my problem is the same.

Evrything works as supposed but output is extremely low. I've double and triple checked everything, swapped some Jfets (2n5458, j201), checked the pinout. Tried another LM308.
I had 0.47uf caps where should have been 4.7uf, did those, i had lifted one pad on the pcb while soldering, fixed that, I had bridged the output cap, fixed that also (i originally did this in a hurry=)).
Voltages measure correct. Probing tells me that the signal is strong out of the IC pin6-<4,7uf but weak after 1k resistor?
Should i try to replace that resistor or would someone have an idea where the problem emanates?

Thanks

[petemoore]

Should i try to replace that resistor or would someone have an idea where the problem emanates?
  Sounds like a hassle, probably reads about 1k in circuit.
  If Pin6 is output, measure resistance to ground there, sounds like something is pulling the output down.
  what is 'correct voltages'? 
  They usually get to working with the AProbe and Vmeasurements, plus just dogmatically applying the DMM around the problem area to verify everything that is shown on the schematic and nothing more...caveats being that resistors in circuit may occasionally measure low because of an alternate path...anyway that's how I pull hairy problems out sometimes.
  Then do you have a polarized capacitor for output capacitor, has it been reverse polarized for split second or is it turned around and what does probing or injecting signal tell you about what gets through that cap.
  Have you 'beep moded' through the output switching to verify with the DMM that the - side of the output cap can connect to...whatever say volume control, then whatever say IIRC switch, through switch to jack, jack tip isn't grounded etc.?
  I guess you used a DPDT or 3PDT.
 

[OscarMeat]

Thanks for chipping in.

I mean by correct voltages that these are what I'm expecting. Output cap is a electrolyte, negative side facing output.
I'll trace those things you suggested, hope something will pop up. I'll post here if i get it working or find something cool when poking it=)

[OscarMeat]

Problem solved!

Beeping around with  DMM showed me that one of the diodes(1n914) was busted. It bled everything through both directions, so the signal was leaking to ground thru that.
While i was at it I put in a switch for the diodes. 1n914 or red leds.
Sounds sweet, as Rat always does