Lowrider problems - sound but no octaves [solved]

[GhostofJohnToad]

1) Project - Lowrider
2) Problem Description - Sound is more of a tone control coming from UOCT1, DOCT1, DOCT2.  No octave.  CLEAN pot functions as it is supposed to.  Turning UOCT1 down acts a volume control.  Trim pot does nothing.
3) Steps Taken -

• Verified no solder bridges
• Confirmed board has power - Pedal works on bypass and engaged.  Board has power  and is outputting sound

4) Substitutions -

• followed recommendations of build sheet for "leaving C12 off, and using a 1n instead of 10n for C10"  I put jumper wire in place of C10. Hmmm, Could this jumper be the issue  Just realized, Should I have left the spot empty?
• Did not have 160K for R55 so used (2) 82K in series
• Did not use Small Bear CD4013BCN used CD4013BE from Mammoth

C10.

When I get home tonight I plan to check voltages and compare to the readings from a working LowRider I found in another post.  Regarding this, what are the little probe points designed on the board supposed to read?

[Hangingmonkey]

I dont think its the ICs, I used both CD4013BCN and CD4013BE to see if any difference and there was none.

Did you mean jumper wire in C12?

[LaceSensor]

get rid of the jumper and see what happens.
i think thats likely an issue

[GhostofJohnToad]

I dont think its the ICs, I used both CD4013BCN and CD4013BE to see if any difference and there was none.

Did you mean jumper wire in C12?

Yes sorry, jumper wire in place of C12 not C10.

[Hangingmonkey]

Ditch the jumper. Just had a look at mine and the pads are unpopulated.

[mgwhit]

Yeah, the jumper at C12 is dumping all of your upper octave signal to ground and providing a short path to ground (through the upper octave pot and R49) for your clean, down 1 and down 2 signals, leading to it working like a volume control.

[GhostofJohnToad]

I will snip it out when I get home and report out.  I appreciate the responses, thanks all.  Thanks for confirming Hangingmonkey that yours is unpopulated.

Also , thanks mgwhit for explaining the "why" behind what's going on by having the jumper there.  I was looking at the schematic trying to think through what having the jumper there would do.  And that all makes perfect sense.

[GhostofJohnToad]

Clipped the jumper at C12.  It appears to be working but it sounds like garbage.  The upper octave is distorted and fizzy beyond belief.  Setting the trimpot as described in the documentation does nothing.  Regardless where I turn it there is no difference  It is fuzzy at max, mid and min..  The lower octaves only appear to exist as added bass response and don't activate unless the upper octave is turned up at least a little.   It sounds nothing like the demos I have heard.  It's just farty and fizzy.  It's more like a bad fuzz pedal than octave. 

[GhostofJohnToad]

Holy Crap!!! I was just checking voltages across ICs when all of a sudden C22 just popped it's top.  Spitting ooze.  Luckily I had glasses on cause it was big.  It was a 25v cap.  What the hell is going on??? Aw shitty, looks like the cap was reversed.    .  Well at least I have something pointing me to the problem...

[GhostofJohnToad]

Fixed the flipped cap, and sounds just like it did before.

Next step - Did a comparison to nzCDog's working voltages from this thread...
http://www.madbeanpedals.com/forum/index.php?topic=5239.0

There are are some differences that I have highlighted.  At this point I am uneducated enough to understand what might be causing them.  Any help anyone???

IC1
1. 5V       5.04v
2. 5V       5.04v
3. 4.9V    2.48v
4. 0V       3.01v
5. 4.5V    5.04v
6. 4.99V   5.04v
7. 5V       5.04v
8. 9.1V     9.33v

IC6
1. 5V        5.04v
2. 5V        5.04v
3. 9.1V     5.01v 
4. 5v        9.32v
5. 5V        5.04v
6. 5V        5.02v
7. 5V        5.04v
8. 5V        5.04v
9. 5V        5.04v
10. 5V       5.04v
11. 0V       0v
12. 5V       5.02v
13. 5V       5.04v
14. 4.86V    5.23v

Q1
D 9.1v        0v
S 5.32v      4.92v
G 4.3v        2.5v
   

[alanp]

IC1 - pin 4 is supposed to be tied to ground, and therefore 0 volts.

IC2 - pin 4 is supposed to be tied to 9 volts. Pin 3 is supposed to be tied to Vr, or roughly 5 volts.

Q1 - drain is supposed to be tied to 9 volts.

Trace your soldering, something is bridged, or something is not connected in the power distribution.

[GhostofJohnToad]

Pulled out the loupe and I've gone over the board at least 4 or 5 times, I cannot see any bridges.  This is haunting my dreams.  I get what you are saying alan just can't find it.  Would Q1 being bad cause my voltage readings?

[mgwhit]

Don't get hung up over your IC6 voltages -- yours appear to be correct -- but alanp is right about IC1:pin3 and your Drain on Q1.  My best guess: cold solder joints.

If IC1:pin3 were properly connected to ground, you would have 0V there, but you don't and other ground points appear to be okay.  So there's either a cold joint or a broken trace cutting it off from ground.

Likewise with Q1:drain.  Other +9V points have correct voltage, but this one point has 0V.  Either a cold joint or a broken trace.

[GhostofJohnToad]

Retouched nearly every joint that could be suspect.  My voltages now look very similar.  But the sound is absolutely 100% the same.  Just like I turned the treble down and turned up the bass.  I'm attaching a pic too.  Maybe someone might see something I'm not.

Working    Mine
IC1
1. 5V       5v
2. 5V       5v
3. 4.9V    2.48v
4. 0V       0v
5. 4.5V    3v
6. 4.99V   5v
7. 5V       5v
8. 9.1V     9.3v

IC6
1. 5V        5v
2. 5V        5v
3. 9.1V     5v
4. 5v        9.3v
5. 5V        5v
6. 5V        4.75v
7. 5V        5v
8. 5V        5.1v
9. 5V        5v
10. 5V       5v
11. 0V       0v
12. 5V       5v
13. 5V       5v
14. 4.86V    5.1v

Q1
D 9.1v        9.3v
S 5.32v      4.9v
G 4.3v        2.5v

[madbean]

Did you mention what transistors you used?