SOLVED The uses of patience (malachite overdrive)

[comradehoser]

Built it. Bypass, no signal. The classic.

Checked to see if my 9v was correctly installed (that was the duh issue for my last troubleshoot). All good.

Solder points at the jacks and switch. All good.

Look at all of my joints. All good.

Bust out the meter, measure the jack, and IC voltages. All good, 9.2v at jack and pin 8; 0 at pin 4 and continuous with ground; 4.6 down the line for the rest.

So it's a signal issue. Bust out the audio probe. Signal stops at the 47p, second capacitor in the signal line. Nothing on either leg and nothing after, but full signal on the previous cap. Continuity on each leg between the caps. WTF???

And it's at this point that you realize you shouldn't have rushed to assume certain things and should have done the very first thing right and in order instead of jumping on flailing about: visual inspection of the whooole pedal.

On the component side, I find the oft-rumored yet rarely observed beast of pedal trouble: ye bridge of solder. Right there, see? Lower left hand side, yellow mlcc above the red wima cap and the 100uf electrolytic? Right between the right leg and that 47k resistor right next to it? That's it. Shhhh if you're quiet it won't frighten.



Needless to say, once the solder bridge was humanely relocated, the pedal perked up in a sprightly way.

 

[comradehoser]

Bonus: my Aion Acoustic 360 Preamp build was pulsing signal. I was like, oh snap, the transformer orientation wasn't very well designated, maybe now I'm going to have to desolder that whole big hunk of stuff.

Busted out my audio probe (saved looper pedal track is clutch), and quickly discovered that it was something all over the power section. 4 seconds of visual inspection later, I discovered that for the very first time in my 100+ assemblies, I put in a (zener) diode backwards. Reversed that and all was 100% basstastique. With an extremely trebly fuzz.