Bluesbreaker Blues

[playpunk]

I am having many problems with two bootiquey bluesbreakers which I recently finished building. One is a KOT clone, and one is a Morning Glory Clone. Both are built on Aion cerulean boards. I have checked and double checked the construction and values of each board, and I am having similar problems with both.

On the KOT clone, I am having extreme popping when engaging the 3pdt. I also am not getting much volume out of the effect. Or at least as much as I'd expect.

On the Morning Glory Clone, i was getting excessive popping when using the switches, (clipping and high cut in this version) and after reflowing the solder on one switch, nada. I was also not getting any(!) clipping.

These two simple builds have me stymied. Should I go through and check voltages and whatnot? Neither problem seems to be related to build or component issues... but I am not a very experienced troubleshooter.

[Nate77]

I've put together quite a few aion pcb projects and Kevin is as solid as they come. I've built myself a single channel KOT (prince of tone ) and I had the same popping when engaging the KOT clone. I've done a ass ton of research and it seams that this is common with this curciut. The output (volume) should be solid. Are you getting the rest of the pots to work as they should? With the MG clone, when reflowing solder, you may have made a tiny solder bridge. If you grounded or connected one pole of the switch to the other you would lose the switches ability to switch between diodes. Do you have an audio probe?

[aion]

I'd doublecheck that the jumpers (one in the top left corner of the board, one bypassing the gain stage toward the bottom) are set properly, as well as the volume pot leg. The thing about the diodes leads me to believe that the op amp jumper might be set improperly, and the popping could be caused by the volume pot leg. Sometimes those get overlooked since they aren't components per se like resistors or capacitors.

Check those against the build documentation and make sure everything's consistent for each variant. I think the KoT and MG will have opposite settings in all three of those places (i.e. a jumper set one way for one, and the other way in the other) but this is just from memory.

If everything checks out, next I would get readings on the voltages for the op amp's pins, as well as the gain stage transistor for the Morning Glory.

Hopefully that gets us someplace! You're in for a treat once you get them going :)

[playpunk]

Hey Kevin:

I checked the KOT board, and I missed one set of jumpers. I put those in and now everything is swell with that effect - still have the pop, but I can work around it now that everything else is so nice. 1n4148 diodes on one side, BAT41? on the other.

I have good voltages on the morning glory, but I think I made at least one truly stupid mistake. Hopefully I will have some time tomorrow to correct it.

[aion]

Sounds good. Let me know if the other one pops as well once you get it working. Someone else had this issue and I'm trying to see if there's a pattern. I may be able to suggest a fix, but just trying to gather some more information first!