# Heartbreaking Paragon Mini troubleshooting...



## PieterSneep (Nov 5, 2021)

So after the initial breakdown of defeat and despair I found this forum and I am hoping you fine folks could lend me a hand finding out what's wrong with my build. It's a Paragon Mini supplied by Musikding, from Germany.

(please pardon my plastic-melting soldering, but I hope you can appreciate the artwork...)









When I first plugged it in boxed:
* Bypass signal works
* When turned ON, there was a thumping sound and the LED would flash on and off along with the thump beat. Think 2 beats per second. 
* Volume and Tone knobs did affect the thump noise. Not sure about Drive, was hard to tell. 
* Same thump noise and flashes for both channels.

I unboxed the pedal thinking the pots shorted somewhere (it's tight in there). Then plugged back in, box open.
* Bypass signal still works
* When turned ON, there was no sound whatsoever on either channel
* Yet the LED's were working on both channels
* I noticed one of the op-amp chips was super hot. Like can't hold your finger on it for more than a second hot. 

I looked up some photos of other Paragon Mini guts and noticed my op-amp chips were faced in opposite direction. Switching both in the direction according to the photos found online, I plug back in







(cover your eyes, this side is bad




* Bypass signal still works
* When turned ON, there is an audible hum, but no guitar signal.
* One channel has way louder hum than the other. But I also made the red channel "hot" and the yellow "normal". Could be that?
* All knobs seem to affect the hum the way you'd expect (volume louder, tone changes), yet again Drive is harder to distinct any changes
* Op-amp no longer gets hot.
* LED's still work both sides. 

That's as far as I got. Is there anything I'm missing? I hope for my sanity's sake it's something obvious and easy to fix ;D 

Thanks in advance!

Pieter


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## Mcknib (Nov 5, 2021)

What voltage do you get to the pcb + and - power pads

It's difficult to see your DC jack wiring clearly


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## peccary (Nov 5, 2021)

I your chips were hot to the touch they are probably fried. I'd get some new ones for sure.


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## PieterSneep (Nov 5, 2021)

Mcknib said:


> What voltage do you get to the pcb + and - power pads
> 
> It's difficult to see your DC jack wiring clearly


Thank you! I will check the voltage at pcb + and - tomorrow when I'm back at the workshop!

Here's a better pic of the DC wiring:





peccary said:


> I your chips were hot to the touch they are probably fried. I'd get some new ones for sure.


Thanks, I'll look into that. I suppose it was only the yellow channel one, so I suppose the red channel should still work?


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## PJS (Nov 5, 2021)

I would be suspicious of any op amp that had been plugged in backwards.  It may be OK, but it may not.  If you have any other dual op amps you can substitute them in - doesn't have to be the same type.  Then at least you can get it working, and order the correct type later if you want to.


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## Username123 (Nov 5, 2021)

PieterSneep said:


> So after the initial breakdown of defeat and despair I found this forum and I am hoping you fine folks could lend me a hand finding out what's wrong with my build. It's a Paragon Mini supplied by Musikding, from Germany.
> 
> (please pardon my plastic-melting soldering, but I hope you can appreciate the artwork...)
> 
> ...


Yeah plugging the op amp in probably crapped it out. You need to get new ones. Every leg of the IC has a specific function and sometimes a component, so if it's backwards you probably fried it. There is no sense in doing anything else until your op amps are replaced.


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## Mcknib (Nov 5, 2021)

Remove your op amps from the sockets  first then check your voltage on the power pads, if it's correct check the voltages on the op amp sockets pins 4, 8, 3 and 5

If the op amps already trashed removing them from their sockets wouldn't really matter but if you've something else causing it like a short you could damage a new op amp

As it stands it's not working taking voltages may lead you to the problem

I'm assuming you've already checked all your component values and orientation are correct, from what I can see all your resistor and cap values are correct 

Make sure non of your DC jack lugs are touching


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## Barry (Nov 6, 2021)

Need to clean that flux off the solder side, and inspect all those solder joints, most of them look cold or overcooked


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## Nostradoomus (Nov 6, 2021)

Yeah…clean your board up first before doing anything. I see a lot of stray solder that could be messing things up. Isopropyl alcohol and a toothbrush are your friend.

Also do a search about building a test box, it can save you aggravation down the road.


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## PieterSneep (Nov 6, 2021)

PJS said:


> I would be suspicious of any op amp that had been plugged in backwards.  It may be OK, but it may not.  If you have any other dual op amps you can substitute them in - doesn't have to be the same type.  Then at least you can get it working, and order the correct type later if you want to.


Thanks, I'll grab some from another pedal and test the Paragon ith those! 



Username123 said:


> Yeah plugging the op amp in probably crapped it out. You need to get new ones. Every leg of the IC has a specific function and sometimes a component, so if it's backwards you probably fried it. There is no sense in doing anything else until your op amps are replaced.


Awawaw such a stupid mistake haha. I'll report back once I've tested with different ones..


Mcknib said:


> Remove your op amps from the sockets  first then check your voltage on the power pads, if it's correct check the voltages on the op amp sockets pins 4, 8, 3 and 5
> 
> If the op amps already trashed removing them from their sockets wouldn't really matter but if you've something else causing it like a short you could damage a new op amp
> 
> ...


Thank you for the list, it is super helpful. Will report back with voltages when I get back to the workshop, but at least I have a plan now : ) 



Barry said:


> Need to clean that flux off the solder side, and inspect all those solder joints, most of them look cold or overcooked


Thanks, will double check! I found this PCB way harder than what I am used to. Smaller contact rings, way more components and tighter spaced. I think it shows on the soldering I was struggling a bit!



Nostradoomus said:


> Yeah…clean your board up first before doing anything. I see a lot of stray solder that could be messing things up. Isopropyl alcohol and a toothbrush are your friend.
> 
> Also do a search about building a test box, it can save you aggravation down the road.


I will look into that. Thanks for the advice!! 

Super thankful to everyone investing their time into getting my pedal to work!! Go team!!


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