Looks like a opamp wrapped big muff with asymmetrical clipping using. One stage has a 1N4001 and red LED, and the other has a pair of 1N4001.
then the second opamp is driving the Octavia style circuit, something similar a Neo-octavia. Just guessing.

daniellp wrote: ↑28 Mar 2022, 21:52 And here is the schematic of the Oxford Sound...

Enjoy with no moderation..

Daniel..

Excellent work! Was thinking about getting one.
These things get a bit noisy, may take a whack at trying to fix that.

I'll try and open up mine sometime soon. Maybe I won't have a white silkscreen on it.

I have mesured value of the California Joyo: +------------------------------------------------------+-------------------------------------------+ | T e c h 2 1 | J O Y O | +---------+---------+------------+-----------+---------+----------+---------+------------+---------+ | Blonde | British | Calif...

Blend wrote:Yesterday I rebooted an MM4 with the simple operation of reset, only now I see this thread. Thanks anyway, it will be useful sooner or later.

Why did the microcontroller need a reset?

brwifrbo wrote:I'll try n draw up a mud map of the board and components over the weekend while ive got it out the enclosure if anyone's interested. My schematic drawing skills are a bit shithouse

Any progress?

I still have the peal, I'll check it out sometime and double check.

Did anyone else ever try this? I never built from that schematic, perhaps there's an error I missed.

Hm, can't seem to edit 2 minute old posts anymore...but since this is a schematic set for repairs, do we have to redraw them? If so, not it!

A normal "Thank you" wouldn't do. That is a huge THANK YOU this one has been on my wish list for quite some time! Sorry, I've been sitting on this for a while, hahah. I forgot I had it. I got it from a friend of a friend. :) I was very surprised it hadn't been posted anywhere else, actual...

Thought this might help for all those capable of soldering SMD stuff. You can at least modify the analog section, and know what part does what now.

This covers several of the Line 6 digital pedals.

I think opamp circuits are always the hardest to put on Vero, haha. I can understand if a layout never gets made, there's a lot going on here, especially with the redundant voltage references.

Here's my single sided layout. Tried to keep the pots close to edge for easy wiring. Couldn't be avoided with the Volume and Tone Pots, though. :( https://i.imgur.com/TYNKU3N.png I'll work on a double sided layout later, should get a bit smaller. This will fit in a 1590BB. I posted my schematic, too...

What, nobody made a single layer through hole yet? :? Is it because it doesn't have Wampler tattooed on it? :mrgreen: Don't make me do it! We will be debugging till the cows come home... :roll: Was just waiting until the correction were released. ;) I'll finish it after work today. Just a bit hard ...

Oh, of course, bajaman. I thought I had missed something awesome again hahah. Yes, I'm working on a single sided layout, been a while since I've done them, since I've been fabbing double sided boards lately. Doing single sided is good practice every now and then hahah. Right now I have one jumper, a...

Well, you need a Vref at the input of the opamp anyway. Actually, I found it quite clever to use the volume pot for that purpose so you don't need the usual high value resistor to Vref. Also, yes, it is asymmetrical Vref (with 2 different Vref, 100k/150k and 18k/47k). It is a nice clipping principl...

Ahh, that's a fair point. :) Looking forward to the corrections, I have a layout that is pretty much done. Just gonna fix it with the corrections. No PCB mount pots this time, but the pots are all by the edge for easy wiring. I have to say, the VREF going to the volume pot is quite annoying. It's ki...

Thanks for all the work, guys! So the gain pot is dual ganged? I may have missed it, but what are the two sets of pads? One is an FX Loop, but there are two? A little late to the party I see... wtf took you so long? Just joking hardy har har... :lol: :lol: Yes, it is dual ganged gain/gate pot... Th...

Thanks for all the work, guys!

So the gain pot is dual ganged?
I may have missed it, but what are the two sets of pads? One is an FX Loop, but there are two?

470J, could be a 47pF capacitor. But the package is strange - might be an inductor.

Actually, if we can see how it's used in the circuit, that may make more sense.