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[brach]

Thank you for making that check. You may very well be right about the pot…But i do think you need to take the microcontroller out and test it again without it in the circuit. What if the microcontroller has an internal short or partial short to ground?…you could get the same test result. Testing components in a circuit can be kind of tricky because you have to consider everything else that is attached to that circuit node. The microcontroller pins are supposed to be high impedance (over 1M) but it is possible for each pin’s internal resistor to become damaged. I’m sorry I mislead you in my previous directions, I forgot about this contingency. And sorry to have you keep working on this, but it’s important to get an accurate diagnosis.
Let me know what you find.
-Brach

[brach]

Poorness,
Good troubleshooting!
You possibly have a bad pot, but there’s also a good chance that the problem is something else, like the microcontroller is injecting 5V on the pot…you just don’t notice it until there is enough resistance on the pot to hold it above ground level.
Test the pot by measuring the resistance of the microcontroller’s pin 24 to ground, when the pedal power is off. It should scale from around 0 ohms to around 100k ohms as you turn it. If it’s is stuck at some high value for most of the rotation then the pot’s bad.
If the pot’s good then remove the microcontroller from it’s socket (very carefully, without bending it’s pins) and power up the pedal…then measure the voltage on pin 24 again as you rotate the rate pot. Test to see if the voltage is scaling as you rotate it. If this works, then the problem is with the microcontroller…or there’s somehow a short between pin 24 and 5V.
Let me know what you find.
-Brach

[brach]

Poorness,
I know it’s frustrating to get done with a pedal and discover that one thing isn’t working right. Sorry for your frustration.
You said that the tap time is working, correct? If the tap footswitch is working correctly then the issue probably is on the analog side of things…meaning an issue with the voltage getting from the rate pot to the microcontroller. On the schematic you can see that the center lug of the rate pot (VR2) is going to pin 24 of the microcontroller. So test that with your continuity tester (with the pedal’s power off). Test it with the meter probe on pin 24 right as it exits the microcontroller’s body, not the solder joint because there could be an issue with socket. If that’s good then power the pedal on and measure the voltage on that pin as you rotate the rate knob. The DC voltage should scale from around 0 volts to around 5 volts as you rotate the knob. If you have trouble with these tests check the solder joints around pin 24 for shorts or opens. You can also test that the left and right rate pot pins are connected to ground and the 5V rail.
Do these tests and let me know what you find.
-Brach

[brach]

Allan,
I’m glad the first issue was so easy to fix.
If the tonality of the pedal is changing over time the only thing i can think of is that it might be a solder joint issue. As in, the signal is being hindered by some bad connection somewhere…and somehow it’s getting worse over time. You can always try to wiggle components with your finger as you play through the pedal to see if you notice the tone changing.
It’s a weird problem that i haven’t seen before. I hate to ask this, but are you sure it’s not your perception or ear fatigue? To test this, you could try to record a riff on your phone when the tone is set the way you like, and then record the same riff again after you play through the pedal for a few hours. That would give you more of an objective opinion about what’s happening.
That’s all i know to say about this issue at this point in time. Let me know if you try re-soldering things or try the recording test.
Good luck.
-Brach

[brach]

Allan,
First of all, are the jumpers soldered properly?
If so, try to test to see if the volume pot is connected properly on the PCB. To do this see if you have continuity between one of the side pins of the pot (the one on the left, depending on how the board is turned) and ground; test to see if the other side pin is connected to one of the pins of C4; then (while the pedal is engaged, ie the red light is ON beside the bypass switch) test to see if the center pin is connected to the output jack tip (or better yet, one of the pins of the relay closest to the edge of the board). For more details look a the schematic in the back of the manual. If all these are making connection then then the volume pot is connected properly and the issue is something else, so start working through the troubleshooting guide.
Let me know what you find.
-Brach

[brach]

The Quaverato should work with any device that sends MIDI messages, but it doesn’t work with expression controllers. The VPM-1, our volume/expression mod for the Ernie Ball Jr pedal, is not a MIDI pedal…it’s only capable of sending expression voltages, so it wouldn’t work with the Quaverato without an expression voltage-to-MIDI converter.
In the lab, we used the Behringer FCB1010 to test and design the Quaverto, as well as the Disaster Area DMC-3XL (which also can convert expression voltages to MIDI). So I know those 2 controllers work, but basically anything that can send MIDI messages can control the Quaverato.
-Brach

[brach]

Good! That was an easy fix!
Take care.
-Brach

[brach]

Email me from our contact page on our website. We’ll try to figure something out.
-Brach

[brach]

I’m pretty confused by your question.
Look at this video (specifically look at the video from 2:20 to about 2:50): https://www.youtube.com/watch?v=OnvNSf8KHvo
How is your bypass switch behaving differently than the one in the video?
-Brach

[brach]

Something is wrong about your power supply. Please measure the voltage across the power supply jack to make sure it is really 9V and not 12V.
On the original power supply you were using (the 9V, 1000mA supply), is the jack polarity correct (positive on the sleeve, negative on the tip)?
Generally, all the intermittent issues (of the pedal not working at all, and then not passing signal…etc) are probably related to bad solder joints. It might help if I could see some detailed, in focus, pictures of both sides of your circuit board. Try to bend the pots up some to capture the solder joints under the pots. If i could see the your solder joints and build quality, I could probably offer some better suggestions as to what direction to lean toward in troubleshooting.
-Brach

[brach]

Stephen,
Work through the troubleshooting guide, step 2.
Let me know what you find.
-Brach

[brach]

Michael,
Contact me via our website “contact” page and let me know your serial number (not in this forum).
I want to check on the warranty status.
-Brach

[brach]

Have you tried any linear power supplies (the old kind of wall wart that has a big, heavy transformer inside) instead of switch mode power supplies (the newer, very light weight wall warts)?

Let me know what you find with the calibration mode.
-Brach

[brach]

I’m sorry to hear about your Quaverato trouble. Thank you for sharing that video, it is very helpful to hear what you are describing. That is a very annoying issue. It does sound very much like a ring modulator.
I have never experienced this particular issue, so we’ll have to try to troubleshoot it together.
First, please try to use a different power supply. A battery would be best to test the pedal out…if you have a 9v battery snap to barrel jack adapter:

…or something like it that would allow you to hook up a 9v battery to the pedal. I’m wondering if the pedal is getting clean enough power, that is isolated enough. This test will see if it is an issue related to the type of power supply that you are using.
Another test you could try is to use “calibration mode” to test each side (high and low) separately of the signal path to see if the issue is caused by the combination of the 2 sides (like a typical ring modulator circuit). I’m interested to see if the weird sound is still occurring when only one side (high or low) is heard.
Try these tests and let me know what you find.
Good luck.
-Brach

[brach]

Sebastian,
I’m sorry about this late reply. The last 2 days were very busy and hectic around here.
Thanks for answering my previous questions. I’m going to assume that your LDR pair is matched (because we matched them when we assembled your kit) so the issue has to be that the LED is not getting bright enough to cause the LDR to lower it’s resistance to a reasonable value.

-Check everything in the circuit between the microcontroller pwm output and the LED. They are: Q1, VR8, and R8.
-Check to make sure the solder joints on these components are good and there are no shorts between any of their solder pads.
-Check to make sure all these components are correct values.
-Make sure R8 is getting 5V on the correct pin (as shown in the trouble shooting guide) and compare the voltage of the other pin on R8 to the same pin on R7.
-Test to make sure the trim pot is working by measuring it’s resistance….from the middle pin to the one of the side pins. Then turn the trim pot about 10 or 12 full turns and re-measure the same pins.
-You should also compare the optocoupler LED voltage (as in the trouble shooting guide…the yellow pads in the voltage chart)…both of them should be around 1.8V.

Look into all that stuff and let me know what you find.
Good luck!
-Brach

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