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So i finished wiring up the Quaverato, and found it to be easy to follow and a fun project. When I plug it in and go to test, I get bypassed sound regardless of what the knobs or switches are doing. The LEDs all are on, and the tap led will change with the rate knob and tap input. After reading some of the other questions on here, I noticed that most of the issues had been with the jumpers, so I tried to redo the jumpers, but got no differnt results. Now I’m afraid I may have burned the pad of JP2.
Any suggestions?
I’m glad you enjoyed you Quaverato build, but that’s too bad about it not working yet.
Are you saying that the signal is bypassed through the pedal no matter if the red bypass led is on or off?…as in you can hear the guitar signal on the output jack at all times? If that’s the case it sounds like the signal isn’t even going through the effect circuit…like the relay may not be switching properly. The jumpers would only matter if the signal was going through the effect circuitry. Don’t worry about jp2 for now, we can always bypass that with a jumper.
If you could send me some (detailed, in focus) photos of both sides of the board to info “at” zeppelindesignlabs.com (if you can’t find a way to post them on the forum), I might be able to see something. Pay close attention to the solder joints of the realay and the microcontroller. You may also want to re-seat the microcontroller in it’s socket to makes sure there’s no problems there.
Good luck.
-BrachCorrect, my bypassed signal is intact at all times. I will get photos in a few minutes. One thing I noticed going over the relay and micro-controller is that I may have put the IC socket in backwards. I have the IC orientated correctly to the circuit (lined up the divots). Socket orientation has never mattered in other builds I’ve done. Could this cause an issue?
A few snapshots
https://drive.google.com/file/d/0Bwt0ZSrjQ0NKNzItamlpZ2hfbFBOSjRIdU4waG02WVViUUk0/view?usp=sharing
https://drive.google.com/file/d/0Bwt0ZSrjQ0NKeUI4VDJwMFZPbnhkWDFBYWlJcUxNelZHOFl3/view?usp=sharing
https://drive.google.com/file/d/0Bwt0ZSrjQ0NKUWZKTzhsNnRBdDdPbVB3OTlydENtd1JzSWtj/view?usp=sharingI re-seated the microcontroller (there were some bent legs that I don’t think went all the way into the socket.) Now when I plug everything in I get straight bypassed signal when disengaged, and no signal when the effect is engaged. Is my signal being sent to ground because of the jumpers not being correctly bridged? How would I go about bridging that with wire if the pads at JP2 are essentially burned off?
Excellent photos. Thank you.
Now it sounds like your relay may be working properly after the microcontroller leads are thoroughly in the socket. Do you hear the relay click when the bypass switch is pressed?
Make sure that pins 15 and 16 are seated properly too because those are the pins that control the optocoupler LEDs.
It doesn’t matter how the socked is orientated as long as the IC in facing the correct way.
If the issue was with the jp2, which is the high frequency signal path, you would still hear the low signal path going through jp1, so i’m not sure that is the issue.
I noticed you have a lot of solder on most of the joints…double check all the solder joints, especially around U2 to make sure there are no shorts. I know you probably are doing this already, but make sure you use the insulation paper under the pots to ensure that nothing is shorted to the back of pots.
Let me know what you find.
-BrachI have checked all of my joints, and while some are a little ahem enthusiastically soldered, there don’t seem to be any unwanted solder bridges. It does occasionally make a noise when engaged, if I am not grounding the circuit, there is a high-pitched hum that pulses with the rate of the tremolo. Still no signal from the guitar though.
How would I check with my multimeter if there are shorts between the IC pins? I am using the insulation paper.Update: I’m not sure how or why, but when I plugged in the pedal this morning (out of enclosure) the effect worked. Very dark tone, but at least it was a start. When I put the PCB into the top of the enclosure, it went back to my original problem of just bypass tone, whether the effect was engaged or not. Also, I am not hearing the relay click now with the PCB in the enclosure. Kind of weird.
Yes, that’s a start! That’s encouraging. It seems like something is shorting…like the back of a pot against a lead poking through the paper. Are you sure no leads are poking through the insulation paper? Make sure you trim all of the leads that are under the pots to ensure they can’t poke through….especially on the relay and microcontroller.
Use some different insulation paper if you need to. I think you are close to getting this to work.
The dark tone is probably from the HIGH side signal path not working due to the jumper issue…we can fix that once it is working reliably.
Keep me posted.
Good luck.
-BrachSo what is happening now is full bypass works, but when the pedal is engaged no input signal is going through at all. I can hear the tremolo effect through whatever signal noise is going through, but there is nothing coming from the input when engaged.
It seems like the relay is working now. This really sounds like the signal path is getting shorted to ground somewhere. I would keep it out of the chassis until you get it all working correctly. So if it’s in the chassis now, take it out and see if that makes a difference. Have you trimmed the sharp leads under the pots? Has the paper under the pots been punctured by the sharp leads?
Let me know.
-BrachWhen it is turned on and you have signal going into the effect, try to gently bend the pots around to see if you can do anything to get signal to come through the circuit. Give special attention to the volume pot…that’s the one pot that has direct control over the output signal. You can also try to poke and press on various components on the board to see if that makes any difference. The goal here it to figure out which component is shorting the signal or keeping it from passing through.
