Tc Electronics Prophet Mods?

hello people!
a friend of mine just gave me today his Prophet delay... and told me about doing a mod that saw on the video linked here (4m :41seg)


wich is apparently the "Glitch Mod" i gues sort of feedbacking one of the modes on the toggle switch..... when moded just the 3/8 section will have this glitch effect..... my question now is.. if is possible to implement the same thing that could affect each mode of the pedal toggle sitch and not just one?

Captura de pantalla 2023-11-15 a las 8.48.50 PM.png
 
Seems like jumpering the time pot would be more effective.
Run another pot 1/10th-1/4 of the original pots value to a dp momentary switch and then from the switch to the two lugs being used on the pot(2 are likely tied together).
That would work in all modes and allow some adjustability.
I'd bet the mode switch is alternating a resistor that is in series with the time pot.
See if one side of the switch dead shorts to one pot leg to be sure.
 
Seems like jumpering the time pot would be more effective.
Run another pot 1/10th-1/4 of the original pots value to a dp momentary switch and then from the switch to the two lugs being used on the pot(2 are likely tied together).
That would work in all modes and allow some adjustability.
I'd bet the mode switch is alternating a resistor that is in series with the time pot.
See if one side of the switch dead shorts to one pot leg to be sure.
Thanks a lot. I can give it a try tomorrow... Could you maybe help me out with a little drawing/ diagram to understand a bit better what i should do? ( Not so much experience yet)
 
Any chance you see the resistance printed on the time pot?
Also, can you post the markings on the other two ICs? Text or photo.
Also, this is going to be pretty tight and require you desolder at least one, if not both of those caps.
You *could solder off the back of the board, like in the original video.
With bending, *There's always the chance we completely bork the board and it's a paperweight.*
If you're in the northern hemisphere, it's getting winter which means static. Which means ESD. This being a TC pedal, 98% bet this it's digital. Need the IC markings to be sure.
Just want to make sure we're all good before we invest time into this...
I'd recommend you have at minimum:
A DMM with continuity, resistance and DC voltage settings.
Quality leaded solder cause this is unleaded ROHS crap and we need to remove it to make it easier to solder to.
Braid/wick(see above)
A decent solder iron(no $5 Walmart job)
Decent soldering skills
Some liquid flux or a flux pen would be beneficial. (I use MG Chemicals 836-Pwith success. On Amazon for $17US. A little pricey but good to have, especially for reworking ROHS stuff)
Clip on leads would be good as well. Again. Not necessary but handy. Especially with those caps next to the pot legs. The little ones you can clip to component legs, not gator/croc clips.

Also, not sure this will be quick because my work schedule is very dynamic, so hang with me there if I disappear for a day or two or post erraticly.
So. If you're good, let's rock. Get me/us the IC labels if you can and the resistance label of the pot if you see it. Probably/hopefully on the side opposite the legs.
 
Man, I really want to just pull that pot out, spin it 180 and wire in a fuzzdog pot swap pcb.
I think there's room to stick a pot out the side there.

Anyone have input here?
That seems the simplist way.
Stick a 9mm pot out the side in the cavity with a pot swap for the time pot.
Is the any chance you can measure the dead space in the box in my(where to video out the new footswitch?
Need at least 25mm horizontal to yes that pcb.
May be able to use a ppcb order switch pcb.
 
Thanks for the help

I have all the stuff mentioned.. hakko soldering iron,flux,solderwick, DMM and even a cheap smd hot air rework station....

I have build quite a number of analog pedals, but this digital world is quite new for me... And my friend just gave me this pedal for that mod in the video... Later he ask if there can be possibly more mods to add on it.. which i thought since is digital,no schematic and to my skills, that theres not so much i can do but i can try asking here for some leads on more possible mods.

I could just find a 22D5 code printed on the side of the pot

So, here are some pictures showing the ic's codes, hope it works.
 

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Yup. All digital.
Looks like. At first glance, same pedal as the echo brain, just a different algo.
Here's an interesting reddit post that basically doing what I'm after here.
But a few more mods.

The pot values used are likely the same between models. I'm willing to be, enclosure aside, they are the same components aside from *maybe* some filtering.

Is try those values at those points, minus the trs jack.
Can always bring the wires out to a breadboard card and experiment with pot values.
You are essentially going to wire the pots in parallel, leg 1 to 1, 2 to 2...
Then put a momentary switch between one of the lugs
I'd recommend wetting your braid with flux(always), and sopping up all the solder off the pot legs you can. Maybe add some leaded solder first, taking your time.
Then wick up what you can, Lift the braid with the iron so as to not lift the pads, flux the pot legs, quickly tin them with fresh leaded solder then tin the wires.
This ensures you get a good liquid flow to attach your wires.
Don't spend too much time on them and space them out time wise. If it doesn't work first time, retreat. Let it cool. Maybe retin and try again.
 
Yup. All digital.
Looks like. At first glance, same pedal as the echo brain, just a different algo.
Here's an interesting reddit post that basically doing what I'm after here.
But a few more mods.

The pot values used are likely the same between models. I'm willing to be, enclosure aside, they are the same components aside from *maybe* some filtering.

Is try those values at those points, minus the trs jack.
Can always bring the wires out to a breadboard card and experiment with pot values.
You are essentially going to wire the pots in parallel, leg 1 to 1, 2 to 2...
Then put a momentary switch between one of the lugs
I'd recommend wetting your braid with flux(always), and sopping up all the solder off the pot legs you can. Maybe add some leaded solder first, taking your time.
Then wick up what you can, Lift the braid with the iron so as to not lift the pads, flux the pot legs, quickly tin them with fresh leaded solder then tin the wires.
This ensures you get a good liquid flow to attach your wires.
Don't spend too much time on them and space them out time wise. If it doesn't work first time, retreat. Let it cool. Maybe retin and try again.
Just to make sure i understood correctly

By that:
(You are essentially going to wire the pots in parallel, leg 1 to 1, 2 to 2...)

You mean: wiring in parallel, the Time and Repeats pots together right?
 
Just to make sure i understood correctly

By that:
(You are essentially going to wire the pots in parallel, leg 1 to 1, 2 to 2...)

You mean: wiring in parallel, the Time and Repeats pots together right?
Yeah and no.
So the original just had a time mod.
What I believe is happening, and you can check the resistance yourself, see below, is the switch is switching one or more resistances in series or parallel with the time pot, effectively altering it's maximum setting/lowering maximum delay time.
Turn the time pot fully clockwise and counter clockwise and measure resistance between lugs 2 and 3, then repeat moving the switch around.
If all reading are different, in relation to switch settings, the switch is adding a parallel resistance.
If all the same, it's adding a series resistance. You can check that my measuring from the switch poles to time pot lugs.
Now, the reddit post added a momentary switch and parallel resistance to both the time and feedback pots. That 2 switches and two pots.
So time pot lug 2 -> new pot 100kB lug 2 ->switch in -> switch out -> new pot lug 3 -> time pot lug 3

You now have a variable parallel resistance for your glitch mod.
I would experiment with the pot value. That's the push button and por on top in the reddit post
The reddit post also added a feedback mod via footswitch, same as before but swap lugs 2 3 for 1 2.
This would add a tunable momentary feedback/oscillation.
Not sure if you have clearance to add a third footswitch so what you incorporate and how is up to you and the clearance you have.

If the 100k pots work well in both cases, you could get a dual concentric pot and stick it out the side in the top part of the open cavity and put one footswitch below it.

Hopefully that's clear as mud.
Ignore the below if you only want the glitch mod.
NOW, if there isn't room for a third footswitch and you want to do both mods, you could use a DPDT momentary footswitch AND a DPDT on on on mini toggle.
Wired correctly, you could toggle between glitch mod/glitch and feedback mod/feedback mod.
That would probably be the cleanest operation wise as 3 footswitches would be really crowded.
So wire as above, each pole of the footswitch for each circuit add the independent poles of the toggle anywhere in the signal flow, doesn't matter, whatever is easiest. Again, on pole per mod.

wire the toggle to:
make glitch, break feedback
Make glitch, make feedback
Break glitch, make feedback

Let me know if you need a drawing.
Where you fit it is up to you.
Obviously the footswitch has to go lower left. I'm adverse to putting pots and switches too close to footswitches. If there's room, I'd stick a dual concentric or 2 9mm pots on stripboard out the lower left side. Maybe a mini toggle can fit up near the LED? If not, it may have to go down on the left side.
 
Conversely, one could use a pair of push pull pots(like those used for coil splits in guitars) and omit the toggle. Pull the pot to turn on the mod, press footswitch to activate.
Or use the dpdt toggle and mount two 9mm with plastic posts above the new footswitch and carefully trim their posts down short so they can't be stepped on easily.
You're /they're not really going to be tweaking them a ton
 
Yeah and no.
So the original just had a time mod.
What I believe is happening, and you can check the resistance yourself, see below, is the switch is switching one or more resistances in series or parallel with the time pot, effectively altering it's maximum setting/lowering maximum delay time.
Turn the time pot fully clockwise and counter clockwise and measure resistance between lugs 2 and 3, then repeat moving the switch around.
If all reading are different, in relation to switch settings, the switch is adding a parallel resistance.
If all the same, it's adding a series resistance. You can check that my measuring from the switch poles to time pot lugs.
Now, the reddit post added a momentary switch and parallel resistance to both the time and feedback pots. That 2 switches and two pots.
So time pot lug 2 -> new pot 100kB lug 2 ->switch in -> switch out -> new pot lug 3 -> time pot lug 3

You now have a variable parallel resistance for your glitch mod.
I would experiment with the pot value. That's the push button and por on top in the reddit post
The reddit post also added a feedback mod via footswitch, same as before but swap lugs 2 3 for 1 2.
This would add a tunable momentary feedback/oscillation.
Not sure if you have clearance to add a third footswitch so what you incorporate and how is up to you and the clearance you have.

If the 100k pots work well in both cases, you could get a dual concentric pot and stick it out the side in the top part of the open cavity and put one footswitch below it.

Hopefully that's clear as mud.
Ignore the below if you only want the glitch mod.
NOW, if there isn't room for a third footswitch and you want to do both mods, you could use a DPDT momentary footswitch AND a DPDT on on on mini toggle.
Wired correctly, you could toggle between glitch mod/glitch and feedback mod/feedback mod.
That would probably be the cleanest operation wise as 3 footswitches would be really crowded.
So wire as above, each pole of the footswitch for each circuit add the independent poles of the toggle anywhere in the signal flow, doesn't matter, whatever is easiest. Again, on pole per mod.

wire the toggle to:
make glitch, break feedback
Make glitch, make feedback
Break glitch, make feedback

Let me know if you need a drawing.
Where you fit it is up to you.
Obviously the footswitch has to go lower left. I'm adverse to putting pots and switches too close to footswitches. If there's room, I'd stick a dual concentric or 2 9mm pots on stripboard out the lower left side. Maybe a mini toggle can fit up near the LED? If not, it may have to go down on the left side.
Oh wow!! Thanks!!

A drawing with we way better for my low skills, of course when possible
 
@jwin615

You're on fire!

hot-guy-sets-world-record-for-running-the-fastest-and-farthest-distance-while-on-fire-without-oxygen.gif


And running with this!

I loved the glitch mod in the Reddit post, I'll have to add that to my Stupor-Dupor Delay mod list.

I wasn't aware of the the Fuzz Dog Pot Swapper, it is a lot more compact than the GPCB 2knob-job.
I need to get a few of those.

The advantage of the GPCB is it accommodates a trimmer as the other pot, perfect for things like runaway delay, as you can dial in the verge-point for a set & forget with just the stomper and no extra external knob required.

If things are really tight, @bilisnegra13, you can forego the Pot-Swapper/2Knob-job board altogether and wire up two pots to the 3PDT "manually".
 
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