MXR - Dime Distortion

resynthesis · Post by **resynthesis** » 20 May 2013, 13:51

I believe it's the same circuit butjust re-drawn. It's legally iffy to post Dunlop's factory schematics hence this requirement. It should sound the same

jimosity · Post by **jimosity** » 07 Jun 2013, 03:41

I've got a Dime Distortion here that I'm trying to repair.
Does anyone have the original schematic they can send me?
The redrawn one doesn't seem to be 100% the same with the part name/numbering.

LucasBrito · Post by **LucasBrito** » 19 Sep 2013, 02:32

Hello guys! I'm new here, and I would like to bring this topic to life again!

Did someone tried this schematic (made by Lobo)? I didn't find the layout, just the schematic.

Lobo, can you share your schematic?

I wish you all the best!

Thanks

LucasBrito · Post by **LucasBrito** » 19 Sep 2013, 02:34

Sorry, my mistake! I wrote schematic, instead of layout... can you share it?

NKLabs · Post by **NKLabs** » 04 Dec 2013, 17:44

So... is there an PCB of this or any layout ?

At first look and after a deeper look the schematic made by LOBO seems to be alright but...instead... im a lazy man when it comes to make a layout or a pcb. To be honest, im looking for something ready to go.

Cheers and happy Xmas and New Year for everyone!

And thanks again for all your work in this forum

NK

Post by **Ice-9** » 04 Dec 2013, 19:05

NKLabs wrote:So... is there an PCB of this or any layout ?

At first look and after a deeper look the schematic made by LOBO seems to be alright but...instead... im a lazy man when it comes to make a layout or a pcb. To be honest, im looking for something ready to go.

Cheers and happy Xmas and New Year for everyone!

And thanks again for all your work in this forum

NK

lol, you say your too lazy to make yourself a layout from the excellent work others have done to make the schematic, but you want someone else to make a layout for you, yeah ok. How about you make a layout and and give something back rather than just wanting to take.

Happy Xmas to you also.

_Dragodinov_ · Post by **_Dragodinov_** » 17 Feb 2016, 14:35

i would like to have mxr dd11 schematic, can some share?

nebuchadnezzar · Post by **nebuchadnezzar** » 19 Oct 2016, 07:08

hi guys, I have a pedal MXR DD11 that was plugged him with the wrong polarity and does not work, I have understood that it is the input diode, I opened and I have to IC view but I can not finish it out I think it has to I see with small holes in the top, I need some extractor? I do not want to break it, nor I can send him since he lost the guarantee to plug in another feeder, please help

nebuchadnezzar · Post by **nebuchadnezzar** » 19 Oct 2016, 07:21

hi guys, I have a pedal MXR DD11 that was plugged him with the wrong polarity and does not work, I have understood that it is the input diode, I opened and I have to IC view but I can not finish it out I think it has to I see with small holes in the top, I need some extractor? I do not want to break it, nor I can send him since he lost the guarantee to plug in another feeder, please help

DrZhark · Post by **DrZhark** » 18 Nov 2020, 16:29

Sorry about necro'ing this post. I'm feeling brave enough to attempt to do the layout and PCB based on lobo's schematic. however I need one last piece of the puzzle: in the schematic, the ICs are only labeled IC1 - IC8, but it doesn't specify which chip is it. I know the pedal uses MC31178 MC31179 and there is one 4016 (IC7?), but they're not labeled the schematic. It also seems there is another op amp in use: IC5A that seems to be different than MC31178 and MC31179.

Any help will be greatly appreciated!

Thanks

deltafred · Post by **deltafred** » 18 Nov 2020, 18:26

I've no idea MC31178 and MC31179 chips are (and neither has Google) but from looking at the schematic -

IC1, 2 & 3 are Quad op-amps (power supplies on pins 4 & 11)
IC4, 5, 6, 8 are Dual op-amps (power supplies on pins 4 & 8 )
IC7 is probably the 4016 (power supplies on pins 7 & 14)

DrZhark · Post by **DrZhark** » 27 Nov 2020, 06:30

deltafred wrote: ↑18 Nov 2020, 18:26 I've no idea MC31178 and MC31179 chips are (and neither has Google) but from looking at the schematic -

IC1, 2 & 3 are Quad op-amps (power supplies on pins 4 & 11)
IC4, 5, 6, 8 are Dual op-amps (power supplies on pins 4 & 8 )
IC7 is probably the 4016 (power supplies on pins 7 & 14)

thanks, you're right, MC33179 is a quad op amp, Mc33178 is dual, so:
IC1, IC2, IC3 are MC33179

IC4, IC5, IC6, IC8 are MC33178

IC7 is the 4016

DrZhark · Post by **DrZhark** » 15 Mar 2021, 18:40

So, I was able to make the board, tested works perfect!

Thanks for the previous posts and the help.

I made a few corrections to the schematic posted by lobo, as I was able to see the first schematic that was later removed

-C4 polarity was reversed
-IC5B pin 6 needs a connection between R28 and R29
-all power and grounds pins on MC33178 were backwards, pin 4 is Vcc and pin 11 is ground
-there was a missing connection between SW2A1 and SW2A2

attached is my final schematic. I hope it helps others. It was a challenging project with smd ICs and a large component count, but the final product doesn't disappoint

: thumbnail_7E0C6850-07AB-4E89-A666-1F9CC76D409F.jpg (74.66 KiB) Viewed 1784 times

: thumbnail_44DD483C-8B10-40FF-99C3-EE15C8E74A55.jpg (99.8 KiB) Viewed 1784 times

: thumbnail_IMG_7051.jpg (110.61 KiB) Viewed 1784 times

: thumbnail_IMG_7052.jpg (143.67 KiB) Viewed 1784 times

MXR - Dime Distortion [schematic]