- August 27, 2019 at 5:14 pm #15911
After setting the gain trim pot and connecting power in preparation for setting the low and high trim pots, my pedal isn’t behaving as expected. The power LED is lit, but the bypass LED will not turn on. I’m reading 4mV at the bypass LED pads on the board and it doesn’t change when pressing the bypass switch. Also, the green rate LED is blinking 1-2 off 1-2-3-4 off 1-2 then off for about 4 seconds over and over. With regards to the calibration, I’m reading open between test points 1&2 and 3&4. Any ideas what I should check first?
DarrylAugust 27, 2019 at 6:47 pm #15913
I think I’ve found my own issue. I replaced the stock pots with alpha pots with dust caps believing this would be enough to insulate them from the board. I just slipped some thin rigid strips of plastic between them and the LEDs are functioning properly. On to calibration and testing!August 27, 2019 at 8:51 pm #15916
Almost there, but I’m still chasing a ghost. I’m still getting the blinking 1-2 off 1-2-3-4 off 1-2 off pattern on the tempo LED intermittently at power up. I can power it on and off repeatedly without touching the pedal and about half the time it does this and nothing else. The other times it works perfectly. I can’t find anything shorting out anywhere. Could I have a flaky microcontroller? Any help would be greatly appreciated.
Thanks!August 28, 2019 at 11:48 am #15935
Sorry I haven’t responded sooner…our server seems to have been down yesterday when i was trying to log in. Sorry.
Anyway, the light blinking sequence is indicating the version of the software on the Quaverato…2.4.2. It’s supposed to enter this “software version” mode when the tap foot switch is held down upon power up. So if your Quaverato is entering this mode randomly then it seems you may have an intermittent short in your tap foot switch connection. Double check the solder joints and even the micro controller socket. When pin 4 of the micro controller is held low (to ground), it is being told the tap switch is being pressed down.
If you can’t find any shorts in the tap switch or anything else, try measuring the voltage of pin 4 to ground to see if it is low (close to 0 volts) or high (closer to 5 volts).
Let me know what you find.
-BrachAugust 28, 2019 at 8:17 pm #15942
Thanks for the explanation of the LED sequence. This makes sense because I did also notice tempo anomalies once or twice where the rate changed abruptly. Now that I know where to focus my attention I will check everything thoroughly. Pin 4 is measuring about 1.8 mV by the way.
DarrylAugust 29, 2019 at 9:07 am #15956
Keep me posted on what you find.
-BrachSeptember 1, 2019 at 8:39 pm #16039
Hey Brach, Sorry it took me a few days to get back to this. I’ve inspected everything closely and I’ve used my multimeter to test. The only time pin is being shorted to ground that I can see is when the tap switch is pressed. Oddly, I seem to be able to get the pedal to work consistently by holding to tap switch down at power up. I’m stumped. Any ideas?
Edit: Scratch the part about it working consistently when holding down the tap switch at power up. That seemed to work for a bit, but was apparently just a fluke.
DarrylSeptember 4, 2019 at 7:30 am #16108
If you are sure that all the solder joints are connected properly and there are no shorts anywhere, it may be that your microcontroller got damaged during assembly. This is similar to other issues I’ve seen related to the microcontroller getting damaged by static electricity, and it seems that it doesn’t take much voltage to disable or damage the internal pull-up resistor on these pins. At this point, it seems that your microcontroller thinks the tap switch is being held down most of the time. If you are able, try re-flashing the microcontroller using our software updater software. If you don’t have the means to do that, you may need to get a new microcontroller. If you need a new one, contact me off the forum we can talk about options…info “at” zeppelindesignlabs.com
I’m sorry about this trouble you are experiencing.