Pacifier not passing sound

[Killstring]

Hi friends. I know that this is probably a case of "build a test rig and go step by step through it," but I'm just so freakin' disheartened.

Some context: I was super into the hobby for a while, then I had some life stuff come up. I'll spare you the details, but I went through a rough mental health stretch; Depression, PTSD, the works. Long story less long, I wasn't really in a good spot to be playing with a soldering iron. And upon trying to get back into it, I just.. geh. Nothing works. Everything is a bad build, nothing passes signal.

This is not, strictly speaking, entirely true. I did build an Amentum Boost, and it seems to work. But anything more complicated than that has been a disaster.

So I know the answer is probably just learn how to troubleshoot, but I've been over this a couple times now. I had one wrong value in C9, maybe there are more? I don't know. Maybe all this soldering is poorly done. But I'm hoping that there's something obvious I'm missing. I could use a win, lol.

So do y'all see anything that jumps out?

It passes sound when bypassed, switching in and out doesn't fix it, the LED gets power.

Thanks, friends.

 

[Nostradoomus]

Looks like the board on the product page is different so I can’t really compare it but there’s no 2n2 caps in the schematic, they’re all 22n.

 

[Robert]

I'll try to get the doc updated for this one ASAP.

 

[Killstring]

Looks like the board on the product page is different so I can’t really compare it but there’s no 2n2 caps in the schematic, they’re all 22n.

That does seem like it's what happened. I'mma poke at this one more time.

 

[Nostradoomus]

I'll try to get the doc updated for this one ASAP.

View attachment 82450

I could still suss it out but yeah

 

[Nostradoomus]

That does seem like it's what happened. I'mma poke at this one more time.

Did you use 2n5088s? Also once the 22n caps are in, if you have a multimeter give us the voltages of each IC. That'll be a good clue.

 

[Nic]

A lot of the solder joints looks cold, some are ball shaped. A good reflow could help. But there are also a few traces exposed, make sure those are not making any unwanted connections.

 

[Killstring]

2n5088s, yeah. I did use JRC4588 IC instead of the KA4588 IC - but I thought that was fine, just a different brand? Should operate the same?

Knew I should have socketed the 2n5088s, though. I swapped out the 2n2s for 22ns: still not passing sound, but maybe I messed things up in the desoldering/resoldering step. I think I need to be more mindful about setting my parts aside before I get started.

I was using lead free solder for about half of it - those joints always look cold to me.

@Nostradoomus - I really appreciate you helping out. I'm gonna call it a night on this one, but I'm feeling vaguely hopeful. I'll update this tomorrow, but I uploaded pics in case anything else jumps out at folks.

 

[Nostradoomus]

Lead free solder is awful

Give the board a scrub with some iso and a toothbrush and we can get a good look.

 

[Killstring]

So, this took longer than I expected, but here we go. Cleaned up & did some reflow.

Iso & toothbrush later, and this is our result. Haven't plugged it in to check yet, but it's hopefully easier to see what's going on.

 

[Erik S]

What’s your test rig setup?

A lot of troubleshooting threads for not passing signal come down to offboard stuff- input/ output jacks, dc jack, stomp switch, or wiring. You obviously don’t have any of that in the pics, so it’s hard to tell what’s going on.

 

[Killstring]

Ahh, fair enough.

I'm using the PedalPCB Auditorium test platform, which passes signal in bypass, and works for other circuits (Arrows, a LPB, a Sproing), so I'm pretty confident it's not the issue. But that's a good shout.

 

[Killstring]

...I am a special soul who's been trying to solder everything at 640 Fahrenheit or so.

Which, having refreshed my knowledge of things, is probably why there's so many cold solder joints.