# Troubleshooting tips and tricks?



## bengarland (Dec 19, 2019)

I'm still learning this stuff, so I apologize if it's an obvious question:

When a pedal doesn't work after building it, what's the general step to figure out what's wrong?

Normally I would do a point-to-point continuity test from input to output to make sure the input signal is working its way around the board properly. Usually I'll find something amiss. But for some bigger builds this can take a lot of time. Is there something more basic that I can check to help locate the problem quicker?

Also, with some of the schematics I'm just confused about where the input signal is going. For example, I'm currently having a problem where the War Scythe isn't outputting any signal (here's the Build Doc). This seems like a "3-in-1" pedal and on the schematic there's IN1, IN2, and IN3... but there's actually only 1 physical input jack. Where do the actual input and output jacks signal go into the schematic? None of the 3 sections of the pedal are working so I think the problem might be near the input or output. And I'm not sure if the way this board is routed if it's an "all or nothing" signal (e.g. if one section had a bad solder joint somewhere, the other 2 sections won't work at all either?)

Any advice is appreciated. Again I'm mainly look for "here's how I would approach this" methodology / tricks from veteran pedal builders and not necessarily specific advice about this particular pedal. I know I can eventually figure this out, but it's a matter of whether I spend 4+ hours probing my way around the board or if there's some simpler and faster methodology I should be using instead. I feel like my soldering skills and general build quality are pretty good, so I get stumped when I put everything together slowly and carefully and it still doesn't work 

Here's a pic of the build -- I did the "Cleft" mod. I didn't put in the stomp indicator LEDs yet because I'm waiting on some bezels to arrive.

My available equipment:

Digital Signal Generator / Counter (new -- still learning to use)
RIGOL DS1054 O-scope (new -- still learning to use)
Standard Digital Multimeter

Thanks!


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## DGWVI (Dec 19, 2019)

Your stomp switches aren't oriented correctly- they're rotated 90 degrees


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## phi1 (Dec 19, 2019)

Here's my quick tips, I'm sure others will chime in too.

First it's best to isolate the problem.  Is it off-board wiring, on-board signal, or on-board DC volatge problem.

For off-board wiring, first off I always like to test the PCB before installing it in the box with the footswitch and jacks.  See the _*test boxes*_ from this thread that make this process really easy.  This way you can see if the signal on-board and power is good, then if you have a problem in the box you know it's the off-board wiring.

For checking the DC voltage, this requires understanding the circuit a bit.  You can check for 9V at the power input and at the other side of the polarity protection diode.  Many builds have a dual op amp, which typically have the same DC voltages.  Any pedals with charge pumps will of course have different voltages.  If you check out the corresponding post from tagboard effects, sometimes there are voltage levels posted in the comments for people who are troubleshooting.
1- 4.5V
2: 4.5V
3: 4.5V
4: 0V
5: 4.5V
6: 4.5V
7: 4.5V
8: 9V

For on-board signal wiring, it's best to build an *audio probe*.  Then you can check different points on the signal path and so figure out where you lose signal.

Keep in mind that a lot of times you will not simply lose signal, but something will not quite sound right.  In those cases the troubleshooting tips still apply, but it can be trickier to locate the issue.  Especially in these cases it is beneficial to understand how the circuit works.  Check out some articles on electrosmash and coda effects that go really detailed into how the circuits work.


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## DGWVI (Dec 19, 2019)

phi1 said:


> Here's my quick tips, I'm sure others will chime in too.
> 
> First it's best to isolate the problem.  Is it off-board wiring, on-board signal, or on-board DC volatge problem.
> 
> ...



None of that will matter until the 3pdts are in their proper orientation


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## bengarland (Dec 19, 2019)

Well... that's... embarrassing. I guess I got lucky and put them in the right way on the previous builds I did. For some reason I didn't think orientation mattered since it is a symmetrical pin layout. I guess I won't make that mistake again! Thanks!


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## DGWVI (Dec 19, 2019)

bengarland said:


> Well... that's... embarrassing. I guess I got lucky and put them in the right way on the previous builds I did. For some reason I didn't think orientation mattered since it is a symmetrical pin layout. I guess I won't make that mistake again! Thanks!


They are symmetrical when the pins are oriented horizontally. Think of it like 3 SPST switches that are all actuated by one toggle


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## Robert (Dec 19, 2019)

bengarland said:


> Well... that's... embarrassing. I guess I got lucky and put them in the right way on the previous builds I did. For some reason I didn't think orientation mattered since it is a symmetrical pin layout. I guess I won't make that mistake again! Thanks!



The boards have since been updated so the 3PDT can't be installed incorrectly.


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## bengarland (Dec 19, 2019)

Robert said:


> The boards have since been updated so the 3PDT can't be installed incorrectly.



Does that mean there are horizontal slots instead of big round holes now?


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## DGWVI (Dec 19, 2019)

bengarland said:


> Does that mean there are horizontal slots instead of big round holes now?


Yup! They're snug, and quicker to solder


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## bengarland (Dec 19, 2019)

I oriented the switches correctly and everything sounds great now! I particularly dig the Ungula part.

But if anyone wants to post some general troubleshooting advice for future reference, please do so...


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## Chuck D. Bones (Dec 20, 2019)

Three words: *Thorough Visual Inspection. * It is the most powerful troubleshooting tool and you don't need any special equipment or expertise.
Most circuit problems are due to workmanship.  Inspect every solder joint under good light and strong magnification.  Double-check component values, part numbers and orientation.  I've been building stuff forever. I always inspect my work and I sometimes find things that need correcting.


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## chongmagic (Dec 21, 2019)

Always inspect the underside of the circuit board solder joints before installing the pots it is much easier to fix something before they are covering sections that may have issues. Learned that the hard way lol.


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