SOLVED First try using audio probe

Dali

Well-known member
Newbie Xtreme here.

I just "build" this high end audio probe (100nf) on the tip.

1621713288517.png

I first tested on a working pedal because every article in the Universe says to use the other wire (red-then-black-alligator in my case to GROUND) and I was not sure about what is ground... (see my level? :rolleyes: )

Then I've checked the schematic (https://docs.pedalpcb.com/project/Delegate-Boneyard.pdf) of the Boneyard Delegate and tried to use some logic. (cough, cough)

Got a loop going in so I don't have to touch a guitar and started using the probe on R1, C1, C2, R2,R3, C104, R101.

Got sound to the amp until I reached C104 (any side of it produced no sound).

Does it means the Electrolyte Capacitor at C104 is "at least" the first culprit to swap/change?
 
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Okay, so lug 3 of the ratio pot is directly connected to C4 and lug 1 of the sustain pot. Pin 1 of the IC is the output A pin of the IC. Pin 7 is the 2nd output. Check that one.
 
Dear @fig you are way more helpful that you wanna acknowledge...

And CORRECTION: Pin 1 on IC1 has no sound. I probably didn't realized I put my finders under the PCB and touch some extra pins when I first tested... My bad.
 
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Now, I am not certain if the LDR needs to be in darkness to test. I can open mine and see if need be.
Like you, I would guess C4, but again..it'd be a guess.
 
Understood. I am cooking myself!

Check the voltage to the OP2134 iC (pin8...around 8.5 vdc...pin 4 should read 0 vdc) to verify the TC1044 is working correctly.
 
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I got 16,90 on IC1 pin 8, pin 4 is zero.

My multimeter is set to 20V (It has those setting: 220m, 2v, 20v, 200v, 600v). Black(COM) on Ground (tried both In and Out, same measure) and Red on Pin 8.

I'm giving you extra detail in case I'm doing it wrong...
 
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I got 16,90 on IC1 pin 8, pin 4 is zero.

My multimeter is set to 20V (It has those setting: 220m, 2v, 20v, 200v, 600v). Black(COM) on Ground (tried both In and Out, same measure) and Red on Pin 8.

I'm giving you extra detail in case I'm doing it wrong...
I was incorrect. It is 17vdc. Do you have another OP2134 you could try?
 
I cannibalized a Magnetron Delay. I tested the delay before switching the OPA2134.

Put it in th Boneyard Delegate and got same results: 17v on Pin 8 and sound with probe on Pin 3.
 
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From this point I'd swap the C4...BUT...I have a tool that makes such tasks nearly foolproof (good thing too). From what I can tell, it'd have to be that or something between it and the node back to the op amp output.

Reminder...fig is noob
 
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