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I have been following along closely, the assembly instructions for the Quaverato. I am at the point where I’m installing the ICs. The socket for the ATmega328PU went in just fine. Then I get to the TL074. I’m wondering why it is not socketed. I have sockets on hand. Would there be any impact by using one?
Thanks!
Alex W
Alex,
Feel free to use a socket if you would like. I just usually don’t prefer to use sockets because they can become oxidized and add resistance to the circuit…it’s just one more questionable connection (or 14, in this case). Soldering a component to the board is usually a much better option if you know you’ll never have to replace it. The reason the uC is in a socket is because some people may want to re-flash the software and sometimes it’s easier to remove the IC to do that…otherwise that would be soldered to the board too. That is just my opinion, but you can do what you’d like.
Good luck.
-BrachThanks Brach,
I went ahead and installed a socket. My concern is always heat damage to the IC. Thank you for responding so quickly!
I’m loving the Percolator amp that I completed recently.
This pedal will add that extra oomph!
Are there any plans for new kits? Perhaps a 5 or 10 watt amp??Thanks again.
Regards,
Alex
I’m glad you are enjoying your Percolator. We don’t have any plans to release another amp anytime soon, but we do have several other things in the works.
Good luck with the Quaverato!
-Brach
Hello Brach,
I put this project down for a short time but now I’m determined to finish!
The pedal turns on. It operates engaged and bypassed. It does add some distortion with increased volume. It does not add any effects.
So no tremolo or harmonic effects. Tap tempo led lights and changes as I tap or adjust pots. I have checked, using the guide, all of the voltages. All are within spec except OPT02 which reads around 4V. When I check it directly, across the two leads, I get 1.8V but when I check with circuit ground connected I get 4V. With My limited electronics knowledge, it doesn’t seem to me that this would prevent the other effects from working. I’m stuck!Are you making it all the way through step 7 in the troubleshooting guide? If so, where on step 8 do you get stuck?
-Brach
Hi Brach, happy Easter!
Well, I’ve gone through the trouble shooting guide again. All voltages are correct. In step 7, I have confirmed orientation and connections for all of the components. I don’t seem to be able to get any effect from the harmonic mix. I have followed the guide to test both but I hear no difference. I was getting distortion when the bypass was off but that was resolved by adjusting the gain trim pot.
I re-flowed all solder joints and re-tested values on many components. Mainly resistors. I did get a voltage reading on pin 5 of U2 of 2.2V instead of 4.5V. I’m not sure where to go from here…Alex
Is the depth knobs set to the maximum value (fully clockwise) when doing your tests? If it is…
Try it in calibration mode to see if both the harmonic mix knob is working and also if the optocouplers are working.
It seems that the analog signal path is working through the pedal but since there is no tremolo effect the LEDs in the optocouplers seem to be on at all times…as if the depth knob is not working somehow (check that the voltage is getting really close to 5V on the center pin of the depth knob). Ensure that the high and low trim pots are set to give maximum LED brightness. You can also check that the LEDs are fully flashing by going through the process described in appendix A.
-Brach
Hello again.
I checked the LEDs and discovered that they are both flashing but I hadn’t properly covered them with the heat shrink. I fixed that, re-checked all of the solder points but still didn’t have any effects. I went through the appendix A. As I said, LEDs work and are properly covered. Both trim pots work. In calibration mode, there is no effect from turning the harmonic mix knob. Jumpers are soldered correctly. TP 1 – 4 all read 5.4V. The only variance I can find is the voltage at pin 4 of U2 is 2.2V instead of 4.5. All of the other pins are at the expected voltages.
Any other suggestions?Alex
If your bypass circuitry is working correctly (step 5-C in the troubleshooting guide) and the LEDs are flashing but you aren’t getting the tremolo effect then you must have a short somewhere in the analog signal path or you are jumping the jumpers wrong. Please check for shorts and make sure the jumpers are soldered correctly (step 6-A in the troubleshooting guide).
-Brach
Brach! Success!!
It turned out that the jumpers were not soldered correctly. Once they were re-soldered, all is working.
Thank you so much for your help… and your patience!Thanks again!
Sincerely,
Alex
