Super '64 OD troubleshooting

pcb rookie

pcb rookie

Active member
Fishing building the Super '64 OD. LED is working fine. I'm getting sound on by pass mode and clean low volume sound when engaged. All pots are turned fully clock wise including the trimpots. I looked at all solders for cold solders, bridge etc. Then cleaned the PCB. I refloweds all sorders, cleaned the PCB before inspecting again. I took some basic voltage mesures on IC, JFETs, Diodes and LED. Here are some pictures. Anything stands out in those values and pictures? This is my fourth built so I do not have much experience or knowledge. I will take all the help I can get! Thank you in advance for assisting with this troubleshoot.

Build docs: https://docs.pedalpcb.com/project/Super64.pdf

IC TL1044SCPA - data sheet: https://www.mouser.ca/datasheet/2/268/21348a-29235.pdf
Pin1: 9.09v
Pin2: 4.84v
Pin3: 0.1mV
Pin4: 131.5mV
Pin5: 0.337v
Pin6: 4.24v
Pin7: 5.61v
Pin8: 9.09v

J201's - data speet: https://www.mouser.ca/datasheet/2/308/1/MMBFJ202_D-2316065.pdf
Pin1/Pin2/Pin3
Q1- 7.71 / 0.39 / 0
Q2- 14.1 / 0.322 / 0
Q3 - 17.72 / 0.635 / 0

Diodes (1N5817) - A/K
D100 - 9.31/ 9.1
D101 - 9.1 / 13.73
D102 - 13.72 / 17.78

IMG_3387.jpeg IMG_3381.jpeg IMG_3375.jpeg IMG_3373.jpeg IMG_3372.jpeg IMG_3371.jpeg IMG_3379.jpeg
 
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pcb rookie said:
I checked the range of the 3rd trimmer. It does sweep from 0 - 47 ohms.

Just finished building an audio probe. I get why it's an essential tool.

I am getting a full volume tone on Q1 and Q2 so tested all the components between Q2 and Q3.

C7 = tone @ full volume
Tone pot and C8 = tone @ full volume
R6 = tone @ full volume
Switch = tone @ full volume on top lug when switched up. No tone on either lug when switched down
R8 = tone @ full volume on one side and no tone on the other
Q3 - Pin1: there is tone but the volume is at least half as loud if not less
Q3 - Pin2: there is tone but the volume is at least half as loud if not less
Q3 - Pin3: tone @ full volume
C9 = there is tone but the volume is at least half as loud if not less

So I decided to decided to reflow the 3rd trimmer and Q3. The solder on pin2 of Q3 acted strange. The solder would not flow. Took the solder sucker and sucked out the solder on all 3 pins of Q3 and ... I think I may have found my problem. I see no contact eyelets on the PCB @ pin2 of Q3 (back side/solder side).

Looks like I'm going to start fresh after all ... unless one of you as another trick up is sleeve. Obviously there's a bit of deception finding out this pedal assembly ain't going work... but I learned a lot through this process thanks to your help so this is very far from a total lost.

Thank you for assisting and sharing your experience. That was very helpful to troubleshoot this project and all the upcoming ones!
Click to expand...

You should be able to hardwire the Q3 source (middle leg) directly to the 220R resistor just below it on the pcb…
 
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I’m
pcb rookie said:
I checked the range of the 3rd trimmer. It does sweep from 0 - 47 ohms.

Just finished building an audio probe. I get why it's an essential tool.

I am getting a full volume tone on Q1 and Q2 so tested all the components between Q2 and Q3.

C7 = tone @ full volume
Tone pot and C8 = tone @ full volume
R6 = tone @ full volume
Switch = tone @ full volume on top lug when switched up. No tone on either lug when switched down
R8 = tone @ full volume on one side and no tone on the other
Q3 - Pin1: there is tone but the volume is at least half as loud if not less
Q3 - Pin2: there is tone but the volume is at least half as loud if not less
Q3 - Pin3: tone @ full volume
C9 = there is tone but the volume is at least half as loud if not less

So I decided to decided to reflow the 3rd trimmer and Q3. The solder on pin2 of Q3 acted strange. The solder would not flow. Took the solder sucker and sucked out the solder on all 3 pins of Q3 and ... I think I may have found my problem. I see no contact eyelets on the PCB @ pin2 of Q3 (back side/solder side).

Looks like I'm going to start fresh after all ... unless one of you as another trick up is sleeve. Obviously there's a bit of deception finding out this pedal assembly ain't going work... but I learned a lot through this process thanks to your help so this is very far from a total lost.

Thank you for assisting and sharing your experience. That was very helpful to troubleshoot this project and all the upcoming ones!
Click to expand...
You say that the 3rd trimmer measured 47 ohm? It should measure 50k ohms give or take 10% so 47k would be fine but not 100x lower. Can you confirm that number.
 
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Coda said:
You should be able to hardwire the Q3 source (middle leg) directly to the 220R resistor just below it on the pcb…
Click to expand...
Mcknib said:
As @Coda says simply solder a wire directly onto Q3 source pin and R7 leg like so, bypassing the damaged trace and directly connecting the components with your wire or you can do it on the underside
Click to expand...
Can't believe it ... It works and it sounds huge! I'll call it a day and box it tomorrow when fresh. Can't wait to dig it.

Would not have made it this far without you guys. what a journey! THANK YOU!
 
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