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  1. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Yes, I have the op amp in correctly (although should have used a socket……). I get good audio from the top pin of r2. Nada from the bottom one. But volume output on the pins now varies from before. Volume on 5 and 3, but low. And I’ve lost overall output now. Only getting it with the probe...
  2. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Good volume on pin 1 (null), 2 (input), 3 (input), 4 (vol - ) and 5 (null!). nada on 6, 7 and 8. I know that’s weird. By far the loudest volume is on the pot pins. I also discovered that the Harry Homeowner who owned our house before us back in the 80’s did a lousy job on the basement...
  3. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    I am definitely getting signal at volume pot pin 1. Pin 2 and 3 also, but as you say volume is louder at pin 3. Tone and gain pots deliver similar volume signal on all 3 pins, except gain pot has no signal on pin 1 (well, it has that faint signal that comes when I put my probe pin near anything...
  4. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    R2 has audio on BOTH sides. Q5 and t get good, loud audio on base and collector pins. Louder on collector.
  5. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Well, I used the PIN numbers per Buddy’s post above (#295), but I’ve noticed some variations in PIN numbers. I’ll check again tomorrow………. And all the pot pins seem the same volume…Loud.
  6. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Well, it’s been an interesting chapter in my saga today. (I was going to call this pedal the Blooz Ooze (long story) when I finally get it working, but given it has become my great white whale, I may call it Moby Lick 😜). Because the volume is so low, I decided to put the audio probe on every...
  7. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Yeah, progress! I get some static and pops and maybe the volume is a little low so more exploration is in order…….
  8. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    You’re not gonna believe this but………..I soldered in a little bridge from q1 source to q3 source, see pic, and now I’m getting audio out to the amp!
  9. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    No continuity between q1 and q3 sources. If I’m looking at it correctly, the trace looks pretty messy near q1.
  10. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Ok, I was wrong. Q1 source is not connected to ground. Also, it’s the lower pin of r6 that’s connected to ground, so that’s ok (I checked all the ground connections as shown on the schematic (at least the first stop from ground) and they are all good. When I check resistance between Q1 source...
  11. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Not as much as me! 😆 I’ll get on it tomorrow! Tks, guys!
  12. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    It has continuity to the source of Q1. No other Q’s. But the same side of the R6 also has continuity to ground (?).
  13. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    It has continuity to the gate of Q5 and the drain of Q1.
  14. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Maybe the missing D100 is causing it?
  15. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    In drain, source, gate order: Q1: 8.6, 4.3, 4.5; Q2: 8.6; 4.8; 4.2; Q3: 9.3; 9.3; 9.2; Q4: 9.3; 4.8; 5.0; Q5: 9.3; 8.0; 9.3; Q6: 9.2; 8.5; 5.0; and Q7: 3.1; 3.8; 9.2. Takes me a little while to get a solid reading on each, bit I think those are accurate.
  16. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Ok, moved the dang pot further out of the way to get better access. I have 0 at pins 4 and 8. 9v at 7. All tracking with you. Pins 2,3 and 6 have 5v. 1 has 2v and 5 has 3v. I do have another IC071 (TL 071CP) and now have some sockets. But if it is now tracking ok, I’d rather avoid the...
  17. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    Ok, I’ll give it a try…….
  18. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    And I’m getting 4v to the gate and source of Q1
  19. Jeff C

    SOLVED Cobalt Drive problems…..SOLVED……..FINALLY!

    O here’s my ‘power’ status now, referring to the power section of the schematic: 100% to the D100 pin (no actual diode there; a temporary bridge wire connects its pins); 100% to C100; 50% to C101; 100% to R101; 0% to R102; 0% to R100; the IC pins all get varying degrees of power (my...
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