freestompboxes.org

it's stated on PCB J201

white IC I don't know

Just picked up one of these. I'll get you guys some better shots up sometime over the weekend. The trannies are J201's but mine are actual TO-92 packaged rather than the SMD version. The white "ICs" are H11F3 optocouplers. The IC is an LM386.There also appears to be a 2N5089 that's part of the tight/big switch.

Brian W. stated on several forums that the idea behind this fuzz was to get the sound of a fuzz into a dirty amp, so I'm guessing 386-based fuzz into a plexi-style JFET overdrive.

Here's a start. Forgive my lack of photography skills.

I'll work on the cap values, since they're a bit hard to see.

Wow! great!
you can desolder the potentiometers and take pictures of both pcb sides in parallell plan (the whole board in one picture to be more clear)? This can help in tracking circuit to make a schematic.
Potentiometer are a easy component to put back later.

After tracking, the values of componentes must be confered.
Thanks man! Great job, again!

Yep, happy to. I'll get to it sometime this weekend. I wanted to re-solder those pots anyway. As it stands, with everything tightened up, the board-mount jacks don't perfectly line up with the holes in the enclosure, so it puts a bit more tension on the PCB than I'm comfortable with.

Sounds fantastic though!

Mods - can we get this moved to the Boutique section since it's well on the way to being traced?

Plastic isolation for capacitor !

This man can surprise me every time !
I really love Mr.Wampler products !

Michael,
pls more pictures and take a note about Caps values.

michaelballard wrote: I'll get to it sometime this weekend.

All things come to those who wait.

wow this is really interesting. 3x J201x, 2n5089, 4x H11F3 and a JRC386. Looks like the switch toggles between the 5089 and the 386

It also looks like he's captured the whole world's supply of H11F3 opto-FETs. I used to use these for muting, routing, and as the gain control element in compressors and limiters! They used to be available from Rapid, Farnell and everywhere else, but all my regular suppliers discontinued them some time ago. They are a really useful device, and I couldn't understand why they were discontinued.

mictester wrote:It also looks like he's captured the whole world's supply of H11F3 opto-FETs. I used to use these for muting, routing, and as the gain control element in compressors and limiters! They used to be available from Rapid, Farnell and everywhere else, but all my regular suppliers discontinued them some time ago. They are a really useful device, and I couldn't understand why they were discontinued.

This will be expensive, for shure.

mictester wrote:It also looks like he's captured the whole world's supply of H11F3 opto-FETs.

Littlediode (http://www.littlediode.com) has a black packaged version of the H11F3 for sale for around £6 in the UK (they are also offering them for sale on eBay).

I've never been turned on fuzz, but I'm getting a definite stirring in my pants with this pedal.

I am going to stick my neck out here and say that I don't believe these Opto-Isolators are essential to the excellent sounds this pedal creates. I think they are just used for switching - and you could always do that by other means. Maybe BW just stuck them in there to delay the time when this forum will have the cracked the schematic. Call me a cynic - but then I AM the devil.

So, I'm guessing it's a four-FET (3xJ201 and a 2Nwotzit) giving the basic drive - probably derived from a ROG design - and then fed into a Smokey (or similar) 386-based amp.

First one to come up with the circuit gets a "Get Out of Hell Free" card.

The 2N5089 is a BJT, not FET, and it is suggested earlier in the thread that the 2N5089 is associated with the tight/big switch. Since the switch is labelled 2N5089/386, it seems reasonable to assume (as was also suggested earlier) the BJT/386 are switched to provide a tight or big fuzz stage, and the 3 JFETs do the amp emulation. However, unless the single BJT is literally just boosting the JFET amp into fuzz territory, the picture is certainly not complete.

Unless Brian comes on here and sorts us out with a complete schematic (Brian! Brian! Brian!), we'll have to wait for some more pictures.

(Also slightly drooling at the sound of this pedal).

Here's a better front and back ...if this doesn't help, I have a 12MP camera I can try with.

I'll get the cap values up later - may have to do some desoldering to get to all of them.

Lucifer wrote:I am going to stick my neck out here and say that I don't believe these Opto-Isolators are essential to the excellent sounds this pedal creates. I think they are just used for switching - and you could always do that by other means.

I really hope you're right, but the 3PDT footswitch daughter board appears to be wired exactly as per input-grounded true bypass - I can't' see how/why the opto's would be worked into that.

Nocentelli wrote:The 2N5089 is a BJT, not FET, and it is suggested earlier in the thread that the 2N5089 is associated with the tight/big switch. Since the switch is labelled 2N5089/386, it seems reasonable to assume (as was also suggested earlier) the BJT/386 are switched to provide a tight or big fuzz stage

Yup, I wasn't paying attention - that's why I didn't have the '5089' bit of the '2Nwotzit' in my head - otherwise I would have recognised that it was a BJT.

I also didn't scrutinise the labelling in the pics, or I would have seen the association of the BJT and OpAmp with the toggle switch.

But hey, it's bleeding dark down here (in Hades) - and I'm over 2000 years old, so my eyesight's not what it was and my memory . . . my memory . . . what was I saying ?

Not hundred percent matched, but maybe usefull...

working on it...
michaelballard thanks for the great pics! if it's ok for you i would ask for some more ones and/or confirmations about some traces on the component(top)-side: there are some areas that are still in the shadow . I'll be more precise in the next posts anyway