SOLVED Dark Rift No repeats?

Petey Pedals

New member
The pedal is working(almost) but the repeat knob is providing only a single repeat on any given setting. I can tell this delay is going to sound awesome since I hear modulation happening. I just need to figure out how to get more than one single repeat. LOL.

I tested the potentiometer B50k repeats pot with my DMM and it’s definitely working like it supposed to. I reflowed all of the solder joints and I tried swapping out every IC and still have the same result. It seems like maybe one of my components might be bad but I’m having a hard time figuring out where the problem is.
Here are the IC voltages I’m currently reading.....
IC1-
1. 4.82
2. 4.82
3. 3.805
4. P
5. 4.80
6. 4.82
7. 4.82
8. 9.62

IC2-
1. 4.94
2. 2.47
3. 0
4. 0
5. 2.831
6. 2.472
7. .740 (fluctuating)
8. .760 (fluctuating)
9. 2.468
10. 2.471
11. 2.472
12. 2.469
13. 2.3
14. 4.93
15. 2.47
16. 2.47

IC3-
1. 2.482
2. 2.495
3. 2.468
4. 0
5. 2.464
6. 2.474
7. 2.471
8. 9.61

IC4.
1. 5.0 (fluctuating)
2. 4.81
3. 4.79
4. 9.61
5. 5.0(fluctuating)
6. 4.69
7. 5.0(fluctuating)
8. Fluctuating between 3.6 & 4.9
9. Fluctuating between 3.6 & 4.9
10. Fluctuating between 3.6 & 4.9
11. 0
12. 4.79
13. 5.0(fluctuating)
14. Fluctuating between 3.6 & 4.9

IC5.
1. 9.62
2. 0
3. 4.94

Thanks in advance to anybody who takes the time to help me figure this one out. I feel like I’m so close!
 

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Hi guys, sorry for the necroposting but I'm having the same issue. The pedal it's working but it's giving just a single repeat. Well actually it's not just a single repeat but the feedback is pratically inaudible except for the first, still low, repetition. I can even tell the modulating it's working but by now this thing it is a useless pedal. I'll post audio on the next comment. I really don't know what the issue can be. I already tried to substitute the chips.
3 things to note in the photo:
I swapped the lm324 with a tl074 to see if i can get any change, but nothing.
D2 it's in reverse to what the pcb tell. I reversed it to try to align to what the build guide says but that still not was the fault.
In the place of R7 there are 2 resistor in parallel that i tested to be 8K (required value is 8.2k, but i don't think that's the problem again)
 

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And here are my voltage:

Pt2399

Pin1: 4.5
Pin2: 2.25
Pin3: 0
Pin4: 0
Pin5: 2.63
Pin6: 2.25
Pin7: fluctuating (average 0.32)
Pin8: fluctating 0.65 to 0.66
Pin9: 2.25
Pin10: 2.25
Pin11: 2.25
Pin 12: 2.25
Pin 13: fluctuating 0.01 to 0.02
Pin 14: 4.5
Pin 15: 2.25
Pin16: 2.25

Tl074:
Pin1: 4
Pin2: 4
Pin3: 2.2 then start to drop
Pin4: 0
Pin5: 3.93
Pin6: 4.02
Pin7: 4.02
Pin8: 8.05

lm833:
Pin1: 2.26
Pin2: 2.26
Pin3: 2.20
Pin4: 0
Pin5: 2.22
Pin6: 2.25
Pin7: 2.26
Pin8: 8.05

lm324:
Pin1: oscillating from 2.5 to 5.something
Pin2: 4
Pin3: 3.92
Pin4: 8.05
Pin5: oscillating like pin 1
Pin6: 3.6
Pin7: oscillating from 1.something to almost 7
Pin8: almostl ike pin7
Pin9: like pin 1
Pin10: like pin 1
Pin11: 0
Pin 12: 3.9
Pin 13: oscillating fom 3.8 to 4.2
Pin 14: oscillating from 1.6 to 6
 
Very sorry I'm new to this forum - what was the solution (where it says "SOLVED")? I've quad checked every value and orientation, and I'm getting exactly the same issue of "one repeat" from last nights build. I saw a recommendation to use MLCC instead of Poly Film for the 1u values (that shouldn't matter at all IMHO) and I've also seen recommendations for 1n vs. 1u in certain positions but not sure others have encountered that. There's an error in the diode direction on my board but they're going to ground so I'm guessing they clip the repeats - I've tried them in all directions and makes sense that didn't fix it. Swapped chips and got the same result.
 
Very sorry I'm new to this forum - what was the solution (where it says "SOLVED")? I've quad checked every value and orientation, and I'm getting exactly the same issue of "one repeat" from last nights build. I saw a recommendation to use MLCC instead of Poly Film for the 1u values (that shouldn't matter at all IMHO) and I've also seen recommendations for 1n vs. 1u in certain positions but not sure others have encountered that. There's an error in the diode direction on my board but they're going to ground so I'm guessing they clip the repeats - I've tried them in all directions and makes sense that didn't fix it. Swapped chips and got the same result.
You should start a new thread with picture of your build. I’ve built three of these and haven’t experienced what you are- hope to help!
 
I’m going to rebuild using different (skinnier) 1u capacitors which will be a tad more photogenic and if it happens again I’ll post. The fat (chiclet) film caps I have in there now would obscure any diagnosis. I really appreciate the reply and offer to help. I’d only post a pic for a laugh. The wild chorus and single echo I do get sound glorious I just want the repeats! I’ve built a disaster transport with the same karaoke chip that I love and had to hear this one too. Thanks again!
 
THANK YOU SO MUCH FOR REVIEWING. I'm still astounded at this community's dedication to the craft.

Those pots are soldered from the other side of the board and working - i will check the solder joints on those caps as you rightly point out but they look solid. I really appreciate the time, thank you and I'll start a build thread for #2 if there's an issue, or post a demo if it works. I love this circuit.
 
And on the direction of the diodes D2 abd D3, do you follow the build doc or the screened indication on the PCB? I guess it clips the repeats a little if I look at the schematic.
 
I’m surprised no one mentioned this. It sounds like your 2399 is locking up. Have you tried different ones?
Yes - i tested about 10 different 2399s including the one from this project in a working disaster transport clone and they all worked. Thank you - I’m just going to go very slow and hyper check every step - this one is for a dear friend and i need to get it working. I will post back when I finish the next build
 
2nd build working great thanks again! Out of paranoia I did insulate the legs in the top row of pots from the pot canisters on the bottom - that could have been my problem in the first build but can't confirm - this board is very tight and I noticed the pots I was using were precipitously close to touching one another - it you look at the schematic I was probably sending repeats straight to ground on that first build, as they are passing through lug 2. Anyway - appreciate the support and it ended well - that's the only root cause I can muster - repeats lug 2 shorting to ground on the case of the "shape" pot below it. Great sounding circuit, like a drunken and seasick memory man and then some if that's what you're after!
 

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