# Tyrian Distortion...



## Mourguitars (Oct 16, 2019)

Plugged it to test and R2 10k smoked....

Not having  good results with this series of pedals...lol



https://imgur.com/ZwEG07E


Was able to put 10#s in a 5# box..as CDB put it, had to use header pins and socket the LED underneath ....it test fitted well



https://imgur.com/6JDvPOv


Tacked in a new 10k into R2 but it's dead...

Mike


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## Cybercow (Oct 16, 2019)

R2 is NOT 10*K* Ω. It is a current limiter that should be 10 *Ω*. Un socket ALL of the ICs, replace R2 with the correct 10 Ω value resistor and check the voltage supply section to ensure VCC and VREF are OK. Let us know how that goes.

My guess is that the 10K Ω resistor smoked because it was trying to limit too much current and surpassed the wattage rating of the anticipated 10 Ω rating. If the 10K smoked, other components may have joined it in its leap into destruction. If replacing R2 with the designated 10 Ω resistor then provides proper VCC & VREF values at the measuring points indicated on the schematic, it may be safe to replace all the socketed devices.


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## Mourguitars (Oct 16, 2019)

That's my bad i meet 10R....i glanced at the build sheet , i scribbled it out with a pen, just seen the 10...again great catch!

Ill try a different batch of 10R's i have


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## Mourguitars (Oct 16, 2019)

Nope smoked 10R again....hmmmm ?


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## Mourguitars (Oct 16, 2019)

https://imgur.com/7zIFXP9


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## Cybercow (Oct 16, 2019)

Did it smoke with all the socketed devices pulled? If so, you need to pull and test all the components in the supply section. Double check that C2 nor C4 have shorted. IC1 and IC2 may also be suspect as they are  also directly connected to R2.


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## Mourguitars (Oct 16, 2019)

ill check that ..thanks


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## Cybercow (Oct 16, 2019)

It looks as though IC1 is soldered directly onto the PCB. And it and IC2 are in backwards according to your photos. They will likely need replacing. SOCKETS ! ! ! ! !


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## zgrav (Oct 16, 2019)

You will see some discussion about the pros and cons of using sockets for ICs and transistors.  Especially for people new to the hobby, I think sockets are essential.  First, you may ruin a board trying to unsolder an IC that was soldered in place.   Second, when something isn't working, it makes it much easier to test an IC or a transistor by trying another one.


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## Mourguitars (Oct 16, 2019)

Cybercow said:


> It looks as though IC1 is soldered directly onto the PCB. And it and IC2 are in backwards according to your photos. They will likely need replacing. SOCKETS ! ! ! ! !




I see ....i always thought the ( dot ) goes forward..

I can try to unsolder not much of the legs went thru so a wick or solder sucker it should come out, ...i did replace R2 ....C2...and C4


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## Chuck D. Bones (Oct 16, 2019)

Save the board!  Cut the IC leads, remove the IC and then unsolder the cut leads from the board one at a time.  If the IC is blown (and in this case they are) then they're going into the trash anyway.  Even a bare board is worth more than any of the ICs.  A populated board is worth the board and every component on it, plus the time and effort to install them.  If you're lucky, you didn't burn any traces.  Visually inspect all of the traces leading to both sides of R2.  Look for breaks, burn marks or blistering.  Burnt traces can be repaired.  Film resistors make good fuses.


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## Mourguitars (Oct 16, 2019)

Desoldered and Swapped the Top IC....came out easy, soldered in the RIGHT WAY ! ..put the other in the RIGHT WAY !

Got LED ! ....whew

Now the sound test...great call on the IC's in backwards , went to the eye Dr and need Prizm glasses...

Need to change my name to Mr McGoo !...lol


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## Cybercow (Oct 16, 2019)

With bothICs in backwards, they may BOTH have been fried. I'd use fresh ones to be sure.


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## Mourguitars (Oct 16, 2019)

?    works !

Thanks for the help guys ! 

Mike


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## Mourguitars (Oct 16, 2019)

Cybercow said:


> With bothICs in backwards, they may BOTH have been fried. I'd use fresh ones to be sure.




I did...and C2 and C4 and R2, ...sounds good !

Putting it in the enclosure now


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## zgrav (Oct 16, 2019)

there is no real "forward" or "backward" when placing an IC on a board -- follow the build document.


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