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Hello,
I just completed my build of the Quaverato. I double checked all components on VOM before installation and solder joints are all solid. I’ve been building tube guitar amps and pedals for about 20 years so building this was fairly easy. I’m getting between 0 and 5 VDC on Pin 23 of the microcontroller as I adjust depth but the pot does not do anything EXCEPT at two specific locations the pedal produces the expected tremolo. That’s about 10 and 2 o’clock.
I pulled board from chassis to eliminate any shorting on the pots.
I’m guessing based on other posts that my microcontroller is toast. That’s a shame considering I discharged myself before handling by touching a very large steel rolling toolbox. This usually does the trick when I’ve handled other sensitive components.
I’m on a Mac. How do I go about re-flashing the microcontroller.
Thanks much
AndyAndy,
I’m sorry to hear about your Quaverato issue. By the symptoms, it does sound like the microcontroller is damaged. You can try to re-flash it if you can borrow a PC, but if the microcontroller has been badly damaged it may not be flashable anyway. Otherwise, you can either get another microcontroller from us (contact us via email: info “at” zeppelindesignlabs.com). If you are into building electronics, you may have another atmega328p around, which you can flash with our software…if you can borrow a PC. If that sounds like too much of a headache, contact us and we’ll sell you a new microcontroller.
Once again, sorry for the trouble.
-BrachHi Brach,
Thanks for replying.
Since it’s roasted I want to take a stab at flashing it just for giggles. I have a PC laptop from work. Is there an FAQ on how to do the flashing? Hardware needed? etc…
Thanks
AndyUh oh – I may have the same problem. Everything went great with the build 🙂 However, when I tested with an amp, I noticed the green LED stayed fully lit regardless of any settings, and I was not getting any tremolo effect. After fooling around with all the controls, I noticed a correlation between the Depth control and the green LED. I could get everything working only when the Depth control was between approximately 10:00 and 2:00. The signal still drops out through that range, but re-engages with some small Depth knob wiggles. And when it’s working, all of the other knobs and toggles operate as expected.
I reflowed the solder to the Depth pot, adjusted the paper barrier, and made sure the ground wire from the tab to the board was in good shape.
My unit is ZD3773, and it has the MIDI option (which I have not properly tested, yet).
Do you think it’s the microcontroller? (I’m also on a Mac, so re-flashing doesn’t appear to be an option.)
Thanks!
Grady
Grady,
That doesn’t sound like the microcontroller to me. If it was the microcontroller, you’d have more problems…the other features wouldn’t be working properly….but i may be wrong. To me, it seems like a bad solder joint somewhere. Start by re-flowing the solder joints on the depth knob. But just for good measure check to see what voltage you get on the center pin of the depth pot (or pin 23 of the micro)…you should be getting from 0v to 5v as you turn it up (from counter clockwise). Also make sure the micro is seated in it’s socket very well.The microcontroller is seated properly. I get 4.97 at pin 23. And I get 0 to 4.98 on the middle lug of the Depth pot.
So, I probably don’t have enough solder somewhere, or an errant blob somewhere! Since there is this apparent crosstalk between the Depth knob and the green Rate LED, can you give me a good starting point to look for solder errors? Or, can I use the DMM to track down the cause of the intermittent signal?Is the voltage on pin 23 changing as you turn the depth knob? It should be connected to the center pin of the depth knob. Make sure your meter’s probe isn’t touching any other pins on the micro when you are testing pin 23.
-BrachToday, the voltage remained steady at 4.98 on pin 23 while I turned the Depth knob. I grounded to to the chassis with an alligator clip to eliminate (or at least reduce!) the chance of error while I had the probe on the pin and turned the Depth knob. As before, the only change was that the Rate LED would start blinking at spots from 10:00 to 2:00 on the depth control.
The only other observation I can offer is that if the probe slipped between pins 27-28 or 28-1, the Bypass LED illuminated.
– Grady
That does seem strange….double check to make sure you are really testing the correct pins.
Also, check for continuity between pin 23 and the center pin of the depth pot. If the center pin of the depth pot is changing, pin 23 should be changing too, unless that connection is broken somehow.
You also may want to use a ground point on the PCB…like the point where the grounding wire is soldered…just in case the ground lug isn’t making good connection with the chassis.
-BrachI did, in fact, goof 🙁 I was testing the wrong pin. But, I got it right tonight 🙂 Thanks for the redirection.
There is continuity between the middle pin of the depth pot and pin 23. And pin 23 measures zero to 4.988 as the depth knob is turned from min to max.
Is there a likely culprit (like stray solder) for connecting the depth pot to the rate LED? Everything works well once the rate LED starts blinking, including the tap switch. But thorough most of of its range, the depth control makes the rate LED stay on.
I appreciate your help diagnosing the problem. I’ve built around 10 pedals so far, and only one has been a complete disaster. But, clearly, I’m still learning the ropes. Oh, and I’m building your Altura right now. So far so good!
-GradyNow as i’m interpreting this depth knob issue with more info, it’s sounding more and more similar to the other guy’s issue at the top of this post. So i’m thinking it probably is the microcontroller. This is a weird problem and it seems like something with pin 23’s ADC got damaged somehow. The only recourse right now is to get a new microcontroller…or you can try re-flashing it, if you have the means. Otherwise, contact us (via email) about getting a new microcontroller.
I’m sorry about this. I really hope your experience with the Altura goes better.
Take care,
-Brach
