My triple sloths module, which is an amazing source of chaotic modulation, took a dive.

The module initially worked, but the “apathy” portion of the module recently started outputting a constant -12V instead of the ever undulating voltage that I’ve grown accustomed to using in practically every synth patch.

On President’s Day I had a moment, so I visually inspected the board and all my hand soldered SMD connections looked OK. I verified all of the values of the resistors and the position of the ICs. Using the multi-meter I also confirmed all of the connections in the Apathy circuit to ground and the voltage supplies. Everything looked good.

At the end of all of that I wiped down the module to remove all of the left behind solder flux. Plugging it back in it worked!! Great, all done :)

Of course that wasn’t the end of the story, because after adding a few cables it went back to not working. The fact that it was intermittent was an clear sign that it was a non obvious bad solder joint.

Re-flowing the solder with lots of flux was the next step and greatly improved the soldering around the ICs. Another quick wipe down with flux remover and it fired right back up and ran as it should.

Happy ending, nice smooth modulation and back to making music.