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Mangler NPN

Started by k.rock!, June 25, 2011, 06:53:42 PM

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k.rock!

Hey guys!


So I ordered a pair of OC140s from SB which I believe to be NPN (Please correct me if I'm wrong). I am under the impression the Mangler board is meant for a PNP circuitry correct?

So, in this case, I have flipped the power protection diode as well as the capacitors to match the NPN wiring. The rest of the wiring is straight forward as the any other pedal.

Problem I'm having is that for some reason, if I plug in to the input jack I have LED power all the time, although it gets a little dimmer when it's off. And I don't have sound with the pedal engaged.

I have checked the LED wiring. Positive lead (longest) goes to the tip of the DC jack along with the main power that goes to the board. Negative lead of the LED to the main switch which connects it to ground when the effect is engaged.

This little problem happens only when I have the input connected. If I only connect it to the power supply, it works fine (LED turns on and off as it should).

My input jack has the ring connected to the Black lead of the battery and the Sleeve connected to ground. I have played with the ground locations connected to the Sleeve (straight to the ground on the DC jack or to the main switch).

I should mention that Im using a wiring board from Mammoth which I have used a few times already with success all the time. I have checked all my connections to the board, functionality of the switch as well, continuity, etc....

I'm only suspecting I might have missed something with this project being meant to be built as a PNP circuit.

What do you guys think?

I can post pictures if you need me to.

Thanks!


-Kaleb
God bless!
www.kalebromero.com

dwstanford

Im not sure what's going on, but I had a very similar problem with a pnp fuzz face.  You are correct in that you should just flip any polarized components(caps, diode, led)  If you could post some pictures, I may be of more help.  It may be grounding when engaged, but from what you described, it sounds like you have wired it correctly.  What type of jacks are you using?

k.rock!

I'm using some open frame jacks on it right now. I was using some enclosed jacks from Mammoth and i was having the same issue. I thought it was the jacks so that's why I changed to the open frame.

Here you can see the wiring of the DC jack (sort of) and the wiring board wiring



I'm not 100% sure about these caps with their polarities. Maybe I have one of these reversed?



The board is not shorting with anything on the bottom. That floating wire is the ground wire from the input jack. I was probing around different spots to check if it worked.




-Kaleb
God bless!
www.kalebromero.com

k.rock!

Well consider this one solved! I discovered a tiny splinter shorting the input to ground. :D It now sounds AWESOME!!!

I'll post it on the build reports in a few :)

Thanks for the help!

-Kaleb
God bless!
www.kalebromero.com

gtr2

Oooo, this thing is oozing mojo....  ;D
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k.rock!

Quote from: gtr2 on June 25, 2011, 11:06:31 PM
Oooo, this thing is oozing mojo....  ;D

haha thanks man! I posted a the finished version on the Build reports section :D

-Kaleb
God bless!
www.kalebromero.com

dwstanford

Im glad you got it working.  Looks like a recipe for wickedness.  You're gonna love this pedal.