Deflector no sound, LED does not light up

[Ctrl4Smilerz]

One day I will build a pedal and it will work on the first go, or at least I will be able to troubleshoot it on my own, but for now I must lean on the awesome PedalPCB community one more time. When I plug it in a get a very faint hum, but the LED does not light up, and nothing happens when I engage the 3PDT. Thanks in advance to all the troubleshooting wizards.

 

[Robert]

I believe your wires are connected to the wrong side of the input jack. Those are the switched lugs.

The output jack appears to be correct.

That should solve the hum but won't have anything to do with the LED not lighting.

See if the pedal passes audio after correcting the jack wiring, it could be that the LED is installed backwards.

 

[Ctrl4Smilerz]

Okay, I changed it as you suggested but still no sound. Also when I put a patch cable in and do an audio probe I get no signal to this side, but I get a signal on the other side of the jack. Is it worth bridging the two sides with a jumper cable?

 

[Synchrony Pedalworks]

If you do not get sound on bypass and the circuit, I would look at the footswitch. Is the a solder bridge under the PCB of the footswitch or is the switch bad?

Also, check that power is getting to the board appropriately.

To help figure that out, I would probably test the switch with my DMM with continuity setting. If the switch appears to be functioning well, then use the audio probe to work backwards from the output jack and establish bypass sound (because there is less points of error for bypass). Next, use the probe to work the circuit backwards.

I hope I have been eloquent to not confuse the situation. Good luck.

 

[Ctrl4Smilerz]

See if the pedal passes audio after correcting the jack wiring, it could be that the LED is installed backwards.

If the LED is backwards should I expect sound in bypass, but not when the pedal is engaged?

If you do not get sound on bypass and the circuit, I would look at the footswitch. Is the a solder bridge under the PCB of the footswitch or is the switch bad?

Does not appear to be any solder bridges. Is there a way to know if the switch is bad other than replacing it?

Also, check that power is getting to the board appropriately.
To help figure that out, I would probably test the switch with my DMM with continuity setting. If the switch appears to be functioning well, then use the audio probe to work backwards from the output jack and establish bypass sound (because there is less points of error for bypass). Next, use the probe to work the circuit backwards.

I hope I have been eloquent to not confuse the situation. Good luck.

I will print out the circuit diagram and work through it, step by step. Thanks, I appreciate the help.

 

[Robert]

The only thing that can affect bypass is the 1/4" jacks, wiring, and footswitch itself.

Nothing on the PCB (including the LED and DC jack) would affect bypass.


It looks like I told you wrong about the input jack now that I can see them better in the new pic, it was the output jack that was incorrect.

Switch them both to the lugs on the opposite sides.


For most applications the wires should connect to the lugs with the spring contacts. These are what make contact with the plug when it is inserted.

 

[Synchrony Pedalworks]

Does not appear to be any solder bridges. Is there a way to know if the switch is bad other than replacing it?

Hopefully, Robert’s advice has got you going, but for the future, I will try to answer the lingering question.

I would use my DVM in continuity mode. I would first check the outer lugs. Place one probe on the center lug and place the other probe on a lug on the same vertical column. If the DVM indicates continuity, then flip the foot switch and place one probe on the last vertical lug and keep the other lug on the center lug. Next, repeat the procedure for the other vertical rows.

 

[Ctrl4Smilerz]

Update: I fixed the wiring to the input/output jacks, and then the pedal worked with a slight hiss, which I chalked up to it not be housed. I then changed the polarity on the LED and then everything was working (still with the hiss). I then started rehousing the unit, and the power supply and output jack wires broke. I desoldered it, and cleared out the remain wire as best I could, but I can't get a new wire through.

Rather than pounding my head into the wall, could I daisy chain the ground from the input jack, to the dc jack, to the output jack?

 

[Synchrony Pedalworks]

Update: I fixed the wiring to the input/output jacks, and then the pedal worked with a slight hiss, which I chalked up to it not be housed. I then changed the polarity on the LED and then everything was working (still with the hiss). I then started rehousing the unit, and the power supply and output jack wires broke. I desoldered it, and cleared out the remain wire as best I could, but I can't get a new wire through.

Rather than pounding my head into the wall, could I daisy chain the ground from the input jack, to the dc jack, to the output jack?

When I have not been able to clear the wire, I would just solder the wire onto the tab that remains and forget getting the wire through the hole. Just make sure the solder joint is firm and passes the wiggle test.

When I made drones, all of the wires were soldered on pads and not through holes. The wires would survive many crashes, so it a tried and true method!

 

[Ctrl4Smilerz]

When I have not been able to clear the wire, I would just solder the wire onto the tab that remains and forget getting the wire through the hole. Just make sure the solder joint is firm and passes the wiggle test.

When I made drones, all of the wires were soldered on pads and not through holes. The wires would survive many crashes, so it a tried and true method!

I soldered the wires to the pads and it worked fine, thanks!

Now the pedal is mostly working, but two problems remain. 1) There is a hum whenever the pedal is engaged and frequency of the hum changes with the Density knob. 2) There is a noticeable volume drop when I engage the pedal. As always thanks in advance for all the help.

 

[Synchrony Pedalworks]

I soldered the wires to the pads and it worked fine, thanks!

Now the pedal is mostly working, but two problems remain. 1) There is a hum whenever the pedal is engaged and frequency of the hum changes with the Density knob. 2) There is a noticeable volume drop when I engage the pedal. As always thanks in advance for all the help.

I haven’t built this circuit before, so I am not sure as the the problem. Generally speaking, if I notice an issue with a pot’s control, I reflow all the solder joints that connect to the pot. In this case, reflow the pot lugs, R14-16, C14, and double check the solder joints for IC4. When there is a humming issue, it could be a grounding issue. Lastly, make sure you have the right values placed for the components.

 

[Ctrl4Smilerz]

I haven’t built this circuit before, so I am not sure as the the problem. Generally speaking, if I notice an issue with a pot’s control, I reflow all the solder joints that connect to the pot. In this case, reflow the pot lugs, R14-16, C14, and double check the solder joints for IC4. When there is a humming issue, it could be a grounding issue. Lastly, make sure you have the right values placed for the components.

I reflowed the Density pot and that fixed the hum. @Robert is there a component I can change to get the volume closer to parity?

 

[Synchrony Pedalworks]

I reflowed the Density pot and that fixed the hum. @Robert is there a component I can change to get the volume closer to parity?

Good news! Can you check the polarity on C9? I cannot tell if it is inserted correctly. C9 leads into your mix pot which helps with your volume.

 

[Ctrl4Smilerz]

Good news! Can you check the polarity on C9? I cannot tell if it is inserted correctly. C9 leads into your mix pot which helps with your volume.

Okay that would make sense because those caps didn't have a polarity marking on them, I assumed the long lead was the cathode like on LEDs. I'll have to inbox it and test it with the DMM. Thank you @aefpv, you have been very helpful.

 

[comradehoser]

@Robert is there a component I can change to get the volume closer to parity?

I just built this, and as far as I can tell it's like my ibanez echomachine delay clone in the sense that the volume knob affects the strength of the affected (wet) signal relative to the original (dry) signal, but the overall pedal output remains at unity gain regardless of that mix. Or did you mean to get like a 100% wet mix?

Incidentally, I also fired up the pedal for the first time and it gave me a lot of hiss and whine, particularly when the density pot was turned CCW. I was like consarn this digital damfanglery and was about to put the shoot in troubleshoot until I touched the voltage regulator--it almost burned me--and it was around then that I realized that I had installed it backwards. Flipped it around and it's been all trippy space times since then.

 

[Ctrl4Smilerz]

I flipped c9 but didn't hear any difference. The pedal sounds good but the volume drop bugs me.