hi guys, years ago i posted this:
http://www.diystompboxes.com/smfforum/index.php?topic=96337.msg836884#msg836884

about hacking a digitech whammy iv pedal. the original hack i had done for it worked, or so i thought... i may have been too inattentive (ooh!! SHINEY!!) to realize it was only changing patches in one direction, tho i swear it was working both ways. maybe i was... ummm... not low.

anyways, a cat on the music-electronics forum asked if this hack would go thru all the presets, both whammy and harmonizer, and said in the original video in the linked thread (by someone else) it only went thru one side. i said, no man, it goes thru all of them.

i confirmed that tonite. all the harmonizer and whammy patches and detune patches sequentially with each push of a momentary switch. in one direction with one switch.

but we need two.... one for up thru presets, and one for down. that way you can scroll whichever way ya wanna get to the patch ya want.

i confirmed that it WILL indeed work both directions.

if you short tip connection to sleeve, it will step thru patches sequentially with each press of a normally open momentary switch.

if you short tip and RING together, and then short that to the sleeve, it will step thru patches sequentially in the opposite direction with each press of a momentary switch.

sounds simple enough, doesn't it?



well, for the life of me, tho i can do it with roach clips and jumper wires, i can only make one or the other work at a time.  wt......heck?? 


i was using a spst switch for switch one and two originally, as shown.. and it worked. cheap-ass stupid radio shack ones, the ones that come in the red and black cap two pack. step on one switch, goes up, step on both, it goes down.

someone said if i used a dpdt momentary on the second switch wired as shown but with the other side in parallel with switch one, it would go down without having to step on both switches. so i thought they meant this:



but nope, doesn't work. only in one direction. wtf??

so... my plea.,,, to all ya'll who are way smarter than my burnt out old hippy brain.... how the hell can ya wire this with just two switches?

one switch needs to short tip to ground.  the other needs to disconnect the first switch, connect ring and tip together and short to sleeve (ground).

i am all kindsa confused at this point.  if someone could buy me a clue or three, i'd really appreciate it. i can't understand why it will work without the switches, but won't work with them. confused ?

me too.... hellllllllllllp..... could it be cuz i'm using one spst and one dpdt? shouldn't half a dpdt do the same thing as a spst?? seems to me i'm missing something, there has to be a simple solution... but i messed with this thing for hours tonite, first time i touched it in years... and i just cannot for the life of me figure it out.

Maybe a double-pole?



But that's an extra penny. And leaves a combination un-used. What happens if you short just-ring to shell?

shorting ring to shell/sleeve does nothing. it has to be the tip and ring to sleeve, or just the tip to sleeve.

i tried another pedal i had built for one of my old me5's, same thing... two stupid momentary switches from radio shack.
works fine. i can scroll up OR down as expected.

it has gotta be something to do with the way the switch latches or something, or i'm missing something obvious. what i have now is a double pole double throw momentary... maybe it's the unused half of the switch messing things up? it's really weird.

thanks for the diagram Paul, i will try it tomorrow and see if it works. rock on my friend.

as life would have it some stuff came up that will prevent me from messing with this today, and i gotta gig tonite so it's gonna have to ride a little longer. 
but i DID take a crummy 15 second (all it does) video of the whammy with the hack as originallly portrayed with the crappy radio shack momentary switches... you can see it cycle thru the harmonizer, detune and whammy effects, both up/forward and down/backwards as i had originally reported.
will try and make an honest to god stupid pedal tricks video when it's all said and done...

thanks paul for the help!

haven't had a chance yet to visit the local jobber for a proper switch, so haven't tried paul's wiring yet.

but here's a stupid pedal trick of the unit in action. beware of f-bombs and colorful language, i still swear like an electrician.

Sounds like a job for a diode-OR   

I built one for my Brian May Red Special pedal. I can't remember the functions but based on your experiments it likely was :
tip ->sleeve   (up)
ring ->sleeve  (mode)
tip & ring -> sleeve (down)

Let's call the switches 1 (up), 2 (mode) & 3 (down), each with terminals Y & Z.     connect terminal Z  of all switches to the jack sleeve
connect 1-Y to jack tip
connect 2-Y to jack ring
connect a diode anode to jack tip, cathode  to 3-Y
connect another diode anode to jack ring, cathode to 3-Y

(leave out the mode switch if you don't want it, but I'd have to bet it does *something*)

david