THESEUS - Low voltage to the ICs

[Feezure]

I'm a total noob. One of those guys who thinks he can do anything except for when he runs into trouble, he doesn't know how to fix it. Please forgive me for a couple things. 1) I tried my best to follow the debugging guide, but feel like I've reached a dead-end. 2) Please forgive the few melted edges of wires and stuff, because I was getting sloppy as the hunt for any potential cold joints got into the second and third hour.

I've been tracing voltage through the pedal and have either ~9V or ~18V depending on which power I use. It's all gravy until I hit the 100uf cap on the daughterboard. The output after that is ~1V. When I go to the ICs, they are measuring anywhere from 300mV to 900mV. That seems to be about 10% of what they should be reading. Obviously, when I engage either side of the pedal, it zeroes the output. I've checks the pots too and they are getting continuity. I've gone through every single solder joint to make sure they are rock solid. I've double checked every single component on the board to make sure they line up with the manual.

Hoping for a guru to swoop in, tell me I'm a moron and then point out the obvious solution.

*fingers crossed*

Thanks!

[PRR]

[idy]

Yep, he spotted it. You have 2x47k in the place that needs 47r (on the stomp board) and then the 2x47Rs are on the big board where the 2 of the k's should be.

The 47ohms are there to help keep the power clean and maybe limit current in a bad situation. The 47k are there to divide the voltage for biasing the opamps. One application needs plenty of current, the other not so much.

[Feezure]

Yay! My moron status remains intact. LOL

I'm now getting voltage to the ICs!!! Woooo - but still no output when either side engaged. The pass through is working fine with or without the main board attached.

Any other ideas?

*fingers still crossed*

[duck_arse]

first, welcome to the forum.

second - we don't know what it is we are looking at. please, please, please post all the build docs you have there in front of you. you know it makes sense.

[idy]

Welcome to the forum. Audio probe. Just that. Audio probe. Easy to make. You need one. Got to trace that signal. It dies somewhere. Find out where.

[ElectricDruid]

Welcome to the forum. Audio probe. Just that. Audio probe. Easy to make. You need one. Got to trace that signal. It dies somewhere. Find out where.

Welcome! Once you've got your audio probe sorted out, we can help you find your way through the schematic (hint hint, like Duck said)

http://diy-fever.com/misc/audio-probe/

[Feezure]

Maintaining my moron status I see. LOL

Thanks for being kind.

https://aionfx.com/app/files/docs/theseus_kit_documentation.pdf

I'll get that probe, great idea, thanks!