foot pedal repair

[John]

I am attempting to repair a "homebuilt" foot pedal. Belongs to a buddy, who had it gifted to him by a student years ago. Near as I can tell, the builder took the guts from one pedal and put it into a nifty wooden box. My friend says it "used to work but sort of quit working right after a while, then stopped altogether but sounded good while it worked".

When I got it, it wouldn't light up (LED). After replacing one jack (not the stereo jack) and clipping together some other stuff, I can get it to complete the circuit and light the LED. But here is my puzzle. When I touch the wires together that would go to the footswitch, the LED comes on. Stays on until I touch the wires together again. IOW, I just click them together but don't hold them together, and the LED lights up. Stays lit until I click them together again, and it goes out. The FS that was in it is just your normal on-off switch, no momentary or anything like that.

I'm attaching a pic of the CB itself in case that gives anyone a clue as to what pedal it really is. Oh, it's a fuzz pedal, BTW. Thanks in advance!

[Ritchie200]

Any idea at all what the heck this was in it's past life?  It sure would be nice to dig up the schemo and trace some wires!

Jim

[John]

Not a clue! Reverse engineering will be my last resort 

I'm wondering if there's not a momentary  switch I could use for the FS?

[sluckey]

All my Boss pedals use a momentary switch. The switch is used to toggle a flip-latch circuit. The outputs of the flip-latch control some FETs that actually switch the signal.

According to your description, you should be using a momentary switch also.

[John]

As always,  thank you!

[jojokeo]

It looks like the guts from a MaxonFX pedal removed from it's enclosure and put into a funky oak box? I can't read the writing on the board. What does it say or take a macro picture (using the macro setting) up close to that it isn't so blurry.

[John]

I will do that when I get home. After clipping things together, it works and sounds fine. I ordered a momentary switch and new pots from AES  (only because Doug doesn't have the switch). It was put into a "funky oak box".  The FS was just your standard on/off with screw terminals. I had to chuckle when I was taking it apart, as some of the "after market" stuff looks like exactly what I'd have done before I had any practice - not that I'm much better now!

Story the guy gave my buddy was that "I built this, it's got a tube in it!", etc. When I opened it up I felt sure that he never touched the PCB. Pretty easy to pick out his work from the original. And of course, no tube. But.... it has got me interested in building a tube overdrive pedal, because, you know, I really stay foc -- SQUIRREL!!!

[John]

Here it is.

[John]

Just a followup. I think the reason it quit working totally was a broken wire going to a pot, plus another wire broke as I was de-soldering to move it to the new pot (replaced all 3 along with both jacks). I must say that it sounds quite nice. Goes from a slight boost to a nice smooth overdrive distortion sound, never gets "fuzzy" really. It's all back together, new pots jacks and FS. I'm sure I could have gotten away without new pots n jacks, but when it's open is the time to do it, for the few extra dollars in parts. Thanks again!

[jojokeo]

Goes from a slight boost to a nice smooth overdrive distortion sound, never gets "fuzzy" really.

I don't think Maxon ever made a "fuzz" pedal? Looking at the high parts count, many transistors, and op-amp confirms this. You can call it what you want but 'fuzz' wouldn't be one of them.

The "woody" pedal should now be reliable and last a long time due to your refurbishing.

[Jack1962]

most effects pedals use a latching circuit , that is what it is doing when you touch the wires together it latch's on then you touch the wire together again and it unlatch's.

[super&plexi]

I think he said tube because it's a tubescreamer. a 808 if not mistaken. have him find the box, put it all back together, and put on fleabag(bay) for million$ next to the others. heck I saw my wah in there for 1200. or 2800. another I just got, I saw on there that bidding was over 600, and seller removed it. I couldn't sell myself and get that kind of bread!, but the pedals I grew up on, holy cow! wish I had all my old mutrons, & uni-vibes, echoplexes, ....you can send me 10%. JK. enjoy, it's a cool circuit. do i get a finders thumbs up?.