# General Troubleshooting Tips?



## Bravin Neff (Sep 14, 2019)

I just completed my first build, the Uberdrive. This is based on the Boss SD-1, which I used to own. I can't compare the two directly (I don't own the SD-1 anymore), but something sounds wrong with my Uberdrive. It's hard to explain, but it sounds like the clean guitar signal is being mixed in parallel with the overdriven sound.

Anyway, I am not asking for anything specific, but are there *general* guidelines to follow when troubleshooting? I am in the process of doing the following:

1. Looking for shorts
2. Testing continuities where they should exist.
3. Testing values (e.g., resistance of the pots, capacitors, etc.) to make sure they are right. I did this at build, but it seems I should do it again.
4. Etc.

What I don't know is how to perform is more sophisticated tests, like "check this and this - the voltage should be X." Any tips?

Thanks.


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## Cybercow (Sep 14, 2019)

Bravin Neff said:


> I just completed my first build, the Uberdrive. This is based on the Boss SD-1, which I used to own. I can't compare the two directly (I don't own the SD-1 anymore), but something sounds wrong with my Uberdrive. It's hard to explain, but it sounds like the clean guitar signal is being mixed in parallel with the overdriven sound.
> 
> Anyway, I am not asking for anything specific, but are there *general* guidelines to follow when troubleshooting? I am in the process of doing the following:
> 
> ...


If you have an audio probe, start from the output and work backwards along the signal chain. If you do not have an audio probe, search it on Google and you'll find many simple ones to build and there are YouTube videos available to demonstrate how to use an audio probe. They can be complex or as simple as a gator clip connected to a cap and the other end of the cap is connected to piece of wire with the tip bared.

Most voltage measurements are measured from supply\bias points to ground - depending on the circuit and what is being inspected.

Testing component blues while they are in a circuit is next to pointless as they tend to interact with other components also in the circuit. It's best to lit a leg on 2 legged components to test values.

Also, carefully examine ALL solder connections for potential cold solder joints (they are usually an odd color from the good solder joints) - and also look closely for any solder-bridges.

Hope this helps get you started.


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## Barry (Sep 14, 2019)

First thing I do on problem builds is reflow everything, fixes most issues


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## DGWVI (Sep 14, 2019)

Bravin Neff said:


> It's hard to explain, but it sounds like the clean guitar signal is being mixed in parallel with the overdriven sound.



That's the nature of this type of clipping circuit. It's referred to as "clean bleed"


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## Robert (Sep 14, 2019)

Try replacing the clipping diodes (D1, D2, D3) with 1N4148 or 3mm Red LEDs.

I have this same complaint about most stock "Screamer" circuits (which is what this basically is).


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## Bravin Neff (Sep 14, 2019)

Cybercow said:


> If you have an audio probe...



That was super helpful. I am totally surprised by (1) how much comes up with a google search, and (2) the fact I never heard of one before. Watching youtube videos in action shows that is a super useful tool. Making one now...


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## Bravin Neff (Sep 14, 2019)

Robert said:


> Try replacing the clipping diodes (D1, D2, D3) with 1N4148 or 3mm Red LEDs.
> 
> I have this same complaint about most stock "Screamer" circuits (which is what this basically is).



I just happen to have a few 3mm red LED's lying around... Thank you.


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## Chuck D. Bones (Sep 15, 2019)

Sounds like there may not be anything wrong with your Uberdrive.  But since you asked about troubleshooting...

*Visual inspection is by far your best troubleshooting tool.  *You can find problems quickly and not need a ton of technical knowledge.

Examine every solder joint under magnification from multiple angles.  Looks for these things:
1) missing solder joints
2) cold solder joints
3) leads or pads that did not wet properly
4) solder splashes and solder balls that short pads to adjacent traces, pads or ground plane

Make sure the pots are not shorting to the solder tits.

Visually verify component value & orientation.

I do not recommend "reflowing everything."  Reflowing won't make a good solder joint better, but it can sure make it worse.


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## griff10672 (Sep 16, 2019)

I'll second the Audio Probe .......... it's helped me solve 98 % of the problems I've ever had ( and teach me a crap ton of stuff that goes on in the circuit  along the way ) .... and you can build one in 5 minutes


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