New Pedal Day (Kit build, finally finishing up)

If you're getting some signal then you're not totally screwed. Let us know when you get the solder sucker and want to try again. Once you've reflowed your joints and reconnected that pot if it's still not working we'll talk you through troubleshooting it. We'll measure the voltages and if necessary an audio probe will tell you where the problem is.


So I've got all the pots back on and now that it still doesn't work, do I need to remove the pots to access the pins/pads?

The audio probe thing looks interesting but I'd need to buy more things to make that happen. Not sure if I want to keep spending money on this. I've already spent as much On Tools as I have the kit
 
So I've got all the pots back on and now that it still doesn't work, do I need to remove the pots to access the pins/pads?

The audio probe thing looks interesting but I'd need to buy more things to make that happen. Not sure if I want to keep spending money on this. I've already spent as much On Tools as I have the kit

What would you need to buy to make an audio probe? It's genuinely the easiest way to see where the problem is tbh.

Something you can do now is use your multimeter to measure the voltage of the opamps. That's the ICs listed in the build docs.

Set your multimeter to volts and attach the black probe to ground then measure the voltage at each of the pins. Just write them down and post them here. The correct format for the pin numbers is

tl072-pinout-equivalent.gif


I'm not going to be a lot of help for a day or so, I had an op on my back this morning and I'm pretty spaced out on pain meds at the mo.
 
What would you need to buy to make an audio probe? It's genuinely the easiest way to see where the problem is tbh.

Something you can do now is use your multimeter to measure the voltage of the opamps. That's the ICs listed in the build docs.

Set your multimeter to volts and attach the black probe to ground then measure the voltage at each of the pins. Just write them down and post them here. The correct format for the pin numbers is

View attachment 5761

I'm not going to be a lot of help for a day or so, I had an op on my back this morning and I'm pretty spaced out on pain meds at the mo.
Woah, hope you have a speedy recovery! I appreciate anything at any time you could but I'm not in a huge rush. The excitement of getting it done has died down so this will either be an extremely long project or just end up garbage after a while.

How am I supposed to take these readings? I've got one probe on the ground pad on the PCB and the other touching each leg of the IC, not the pin through the pad. Is this the right way to do it or do I need to flip it over and try from the pad?

1 jumps anywhere between .023 -. 034
2 reads .198
The rest are just zero

In the meantime I've built a crude little table to assist with my own back
16798576062581662883855389780675.jpg
 
Trying readings again from the back where the pins stick out of the pads. Getting actual numbers but they're jumping all over the place
 
Cheers dude. It was a minor op but I'm still pretty spaced out at the mo. There's definitely a problem with your voltages. If you set your multimeter to continuity (the setting where it beeps) pin 4 on the two ICs should connect to ground and should beep.

If you can take pretty good clear shots of the top of the board and the bottom I'll take a look when I'm not so doped up. You're table's pretty cool BTW.
 
If you set your multimeter to continuity (the setting where it beeps) pin 4 on the two ICs should connect to ground and should beep.
It beeps.

Thinking about that audio probe. I'll need everything except for the amp and instrument cables: alligator clips, breadboard cable, 10nf cap. About that 10nf cap, does it have to be electrolytic or can I use a ceramic?
 
I've done a bunch of contact tracing and am getting continuity in most places. I've scraped off a bunch of that dark stuff as well as solder specs.

Watched a few more videos about pedal building and troubleshooting..
Apparently I should have been checking voltages of the ICs with the 9v power on? I was getting some actual readings at that point.
 
Watching.
Speedy recovery to @SillyOctpuss and good luck to @Alex Kenivel!

I'm watching because so far my plans for this year include building (well, rather assembling) my first pedal. My soldering skills might probably be even less existant (basically it's cables, guitar circuits and fixing the occasional lose cable within whatever). So I'm maximally curious how this here turns out.
 
In most cases the issue is with the footswitch. Also those switch daughterboards are an absolute nightmare when they don't work and I'd just recommend avoiding them and wiring the 3PDT footswitch by hand. It's often easy to deform the contacts with too much heat or get bad solder joints on those switch legs causing them to not work.

You can use some isopropyl alcohol to clean up the solder flux residue from the board to make it look nicer and easier see where you might have issues.

I recommend buying a 10x magnification lens too as that can help you see if you have some connections getting bridged by stray solder. It looks like this could be happening around the area between those two B25K pots.
 
Mojo sent. This is why I just buy stuff already built!
:rollsafe
Ha, If I wanted a working pedal I'd probably just buy one. I'm doing this for the experience and a good excuse to drink when I finally throw the towel in for the day.

In most cases the issue is with the footswitch. Also those switch daughterboards are an absolute nightmare when they don't work and I'd just recommend avoiding them and wiring the 3PDT footswitch by hand. It's often easy to deform the contacts with too much heat or get bad solder joints on those switch legs causing them to not work.

You can use some isopropyl alcohol to clean up the solder flux residue from the board to make it look nicer and easier see where you might have issues.

I recommend buying a 10x magnification lens too as that can help you see if you have some connections getting bridged by stray solder. It looks like this could be happening around the area between those two B25K pots.
At this point the footswitch/daughterboard isn't even in the circuit. I just have the I/O Jacks wired to the I/O pads and the battery hooked up to +/-. When it works at this point I'll move on to the switch.

Thanks for the advice, I have a great view with my current lens and I'll check that area today.

Watching.
Speedy recovery to @SillyOctpuss and good luck to @Alex Kenivel!

I'm watching because so far my plans for this year include building (well, rather assembling) my first pedal. My soldering skills might probably be even less existant (basically it's cables, guitar circuits and fixing the occasional lose cable within whatever). So I'm maximally curious how this here turns out.
It's been a learning experience no doubt. My soldering skills sound like yours. Smaller iron tips and thinner solder are a must!
 
And the daughterboard is already soldered firmly (albeit backwards) to the switch so I think I have no choice but to use it unless I want to get another switch altogether
 
I recommend buying a 10x magnification lens too as that can help you see if you have some connections getting bridged by stray solder. It looks like this could be happening around the area between those two B25K pots.

Seconding this!

I've also found that head-mounted close-work lenses are really helpful with this kind of work. And these days, headwear is my preferred way of working (not that I do it much).
 
Getting somewhere. I had a diode connected the wrong way so I fixed that, Brushed off the board with some isopropyl alcohol and reflowed some more solder in some points.

The 9v battery no longer gets hot and the pots seem to be doing something to the signal as I can hear the noise while turning.

Currently retracing contacts, this time marking everything down. I'll throw a few questions in the air, hoping someone might know the answers to these:

Should C3 and Pin 2 from this IC have continuity? (green line connection in picture below)

Screen Shot 2023-04-03 at 11.14.05 AM.png


How do I check this connection Below??

338950895_903269260742840_2743810928168996965_n.jpg


Thanks in advance to anyone who might have some answers!
:beer
 
Idk.. If I just pull whatever parts I can salvage and bin the rest I'll stop sweating about it, stop coming back to it and stop wasting my time. I'm pretty sure I ripped out one of the pot contacts when yanking the pots off to unsolder/reflow.

I'll still have the enclosure, backwards-daughterboard'ed switch, another copy of the PCB. I can probably yank the pots out again. The ICs will come out easy. Any other parts that might be of interest?

I've got a breadboard kit coming to me so I'll just start fresh with some basic circuits. I should have just done that from the start instead of getting in way over my head!
 
I've got a breadboard kit coming to me so I'll just start fresh with some basic circuits. I should have just done that from the start instead of getting in way over my head!

Are you aware of this article here?
Seems like a pretty much foolproof "my first drive pedal for dummies" guide, hence what I thought I'd be going for. It's also completely DIY (instead of using a premade PCB), so that might add to the "it's mine!" sensation.
 
Are you aware of this article here?
Seems like a pretty much foolproof "my first drive pedal for dummies" guide, hence what I thought I'd be going for. It's also completely DIY (instead of using a premade PCB), so that might add to the "it's mine!" sensation.
:facepalm this is probably what I should have started with!
 
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