I want my DOD true bypass, plx help!!11one

G0rilla · #1 08-12-2009, 07:32 AM

Hello folks.
Got a strugle with my DOD FX-72 recently. Some dirt from my boots (yes, i know, i have to be more carefull to my pedals..) got into footswitch, and now its struck. Now it is "always on" flanger. I was using it in my LS-2 loop for a while, but i need LS for other things. So now i have 2 ways (okay, 3, but i want to keep the pedal):
1. True bypass loop.
2. True bypass mod/replace current FS.
And 1. is not going to happen, at least in nearest future, because im too tight on my board already, and finances dont allow me to expand board, neither buy/make looper. And just replacing FS and not making it TB is pretty lame, if i am going to mess with soldering iron.
So, what i want to know (see) is wiring diagram, to make DOD pedal true bypass with 3PDT switch. Note: dont need the stereo output, so it wont be a pain if i lose it.

I have searched for it 2 days, but no luck. And i am not smart enough in electronics, to figure it myself.

bobbass4k · #2 08-12-2009, 07:37 AM

I'd imagine the footswitch is directly mounted on the pcb so replacing it with a 3pdt would be tricky at best, your best bet is probably to get a replacement switch from DOD and just replace it if you feel confident soldering, but if it's just mud couldn't you just take it apart and shake it out?

G0rilla · #3 08-12-2009, 08:16 AM

Shaking out the sand would be a short-term sollution. And anyways, got tired of accidental switching-on of pedal, when, for example, my cord falls on it.
The good news is, its not on PCB. I will take pics today, so you can see that it will be easy, only thing i need to know, i how to wire it.

Thanks for advice anyway!

niftydog · #4 08-12-2009, 07:20 PM

By far the easiest way will be to buy a TB loop pedal and be done with it.

DOD pedals like this use electronic bypass, which you will have to defeat so it stays permanently on. Then, installing a mechanical bypass switch into the DOD enclosure is going to be a monumental PITA which will require custom mounting hardware - in fact I doubt it would even fit in the space available.

To repair the existing switch, first start by cleaning it out. It could be that the dirt is just jamming the mechanical actuator and the actual switch itself is fine.

If you have to replace the switch, don't even bother trying to obtain one from DOD - they are ubiquitous and cheap "tactile switches" which you should be able to find at a half decent electronics store.

bongomania · #5 08-12-2009, 08:09 PM

I'm going to buck the trend here--I think making it TBP is the right idea. However I agree that the existing space in the pedal will make that conversion a PITA. So I'd recommend re-housing the whole thing. Use a Hammond "BB" size box, you should be able to get all the guts, jacks, and a 3PDT switch into that. Then your board will look more kvlt as well.

**TheMutt** · #6 08-12-2009, 09:57 PM

I'd love to know how to do this with another DOD pedal. I have a second FX32 Meat Box incoming to me (retardedly sold the first one, which was a NOS mint in box-er), and it would be great to TBP it.

bongomania · #7 08-12-2009, 11:23 PM

Oh, I love the Meat Box. I have to buy another one of those one day. I've owned (and sold) three of them.

Not knowing off the top of my head where the bypass circuit is, nor having a schematic, what I would do is audio-probe from the input jack through the circuit, while dis/engaging the tactile switch. Ideally there should be an opamp or similar device which connects to both the input path and the tactile switch. That's where to "make the incision" and bypass the bypass.

G0rilla · #8 08-13-2009, 12:46 AM

Yea, i was thinking of rehousing too. Will get out one of these days, and check some electronic shops. Anyways, gonna start doing something, maybe gonna try a "tick" method. Will post the progress.

**TheMutt** · #9 08-13-2009, 03:48 AM

If someone doesn't mind getting paid to do it, I'd gladly do so. Looking at the circuit board, I'm afraid of messing something up.

Anyone wanna do this for me? I'll buy the supplies and get everything shipped to you, pay for your work, and pay for return shipping.

PM me if you're interested.

cheapbasslovin · #10 08-13-2009, 07:53 AM

I modded one for true bypass once. The tactile switch (and wires associated) just comes out completely. The pedal powers up 'on' and the 3pdt takes care of the rest. The input lead and output lead both go directly from their jacks to the board, but IIRC the trick was distinguishing them from the ground leads that are switched at the jacks. Nifty is right, you will need to either modify the box, or rehouse (I found this out the hard way). I don't know that rehousing will help a great deal, unless you a)throw it into a much bigger box, b) mangle the connections from the pots to the board, or c) just rewire the pot to the board, making the whole combination very flexible. The way the board is mounted to the pots, it extends the full length of the pedal and a 3pdt is just too deep to fit in the space alotted between the pot mounting and the board.

I wish I had taken pics of the guts. My memory of the wiring details is really fuzzy.
I think there are 6 solder pads (seven for a stereo pedal) with functions for the In, Out (stereo out), switch, led, +9V and ground. If my memory is right, you remove the switch, run the in, out, and led through the switch via this diagram. You won't need a resistor for the LED as it is already in the pedal. I know that in doing it I broke off every one of the factory wires and had to replace them with my own. They are very fragile. Good luck.

Here's what my finished product looked like:

I really wish I had gotten that car mounted more evenly, but it was a salvage, not an original plan.

G0rilla · #11 08-15-2009, 09:01 AM

Great, thanks, gonna do this myself. Ill post results when its done, and shure, gut picks with them.