True bypass with continuity, but no sound [SOLVED]
So I've got what seems to be a strange issue with a pedal that I just finished building last night. It is wired with a 3PDT switch for true bypass, but I am getting no sound whether bypassed or not. I've checked both guitar cables and they both work fine plugged straight in to the amp. I tested continuity from the input jack part that makes contact with the tip of the cable to the same part on the output jack and have continuity, same for the grounds. So it seems that there is a continuous signal path, but I am still not getting any sound. When I hook the pedal up to a power supply the LED comes on and off just fine, but still no sound whether bypassed or not. All ground points on the entire pedal have continuity and the power supply is putting out 9.1V. I would understand no sound when the circuit is on if something were wired wrong on the PCB, but the fact that I am getting absolutely nothing even when bypassed is throwing me off. I have the switch wired very similar to the picture seen here: http://www.premierguitar.com/Stream/Str ... Type=image I'm at work now and didn't think to take a picture last night so I don't have the exact picture at the moment. Maybe I'm missing something blatantly obvious but I just can't seem to figure out why I am getting absolutely zero sound out of this thing even on bypass. Any input would be greatly appreciated!
Thanks for the replay JustinFun, I will give the grounds another look this afternoon when I get home. I was pretty sure last night that I checked all ground points and had continuity between all of them, but I will give it another look, its always possible that I missed something. I am definitely sure that I checked input jack ground to output jack ground about 500 times last night just because I couldn't understand why I wasn't getting anything even when on bypass. It seems pretty straight forward to me, on bypass I had continuity from input tip to output tip and input ground to output ground, which to me, seems like it should pass signal and produce sound. Thanks again for the input, I'll look over everything again really closely tonight.
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So you are sure the sound from guitar is reaching the pedal - cables tested fing. Next is the INPUT JACK on the pedal:jde111588 wrote: I am getting no sound whether bypassed or not. I've checked both guitar cables and they both work fine plugged straight in to the amp.
If there is continuity between INPUT and OUTPUT, you should get clean signal out, unless there is also continuity between tips and GROUND.I tested continuity from the input jack part that makes contact with the tip of the cable to the same part on the output jack and have continuity, same for the grounds.
So it seems that there is a continuous signal path, but I am still not getting any sound.
You should have continuity between INPUT TIP and INPUT TAB on SWITCH (connected with wire)
Once you find SWITCH INPUT check to which pole it connects in the two different positions.
It might be the INPUT is grounded on the switch or due to bad soldering.
Test the switch like this: connect input tip of jack to input on fx board directly.
Input tip = signal path, should never be directly ground (continuous with ground)
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Thank you both for the replies. Looks like it was indeed a ground issue. I think as I was closing the box up one of the wires got smashed a little bit and I didn't notice it when I was testing continuity after I opened it back up. Somehow I was still getting continuity on the ground path when using a tester, but it wasn't passing signal...still seems strange to me. I tested continuity again on both sides of the wire to be sure I wasn't losing my mind and it tested okay, but I replaced the wire anyway and re-routed it a little bit neater so it wouldn't get smashed and now everything seem to be working great. Maybe is was a bad solder joint on that wire or something. Either way, its fixed and I'm happy with it, so thank you both again, I appreciate your input.