Stuff you wanted to know but were afraid to ask

[jessenator]

Beyond that, if there's not that convenience of already having that spare part, so to speak, is it a general good idea to go out of the way to implement?

 

[ICTRock]

I'm not going to the extra trouble but if you're looking for a meaningless upsell, offering pedals with buffered bias voltage just became your Q4 goal. I still can't believe we got that before tap tempo compression.

 

[apierz]

This thread might give you answers or at least clues.

Thread 'AionFX Monolith - Is my 3P4T daughterboard upside down?'

Mar 10, 2026

Hello!

Recently put together this Big Cheese and noticed that the Mode switch was acting odd, until I realized that the order of the modes were reversed to what I was expecting! The original Big Cheese has the cheese mode on the far left and the tone bypass on the far right so I figured it would be the same here. Unfortunately, AionFX doesn't provide switch position labels in their documentation so I don't know if that is intended. It seems more likely that I buggered up something to cause the order of the 3P4T selection to be reversed. So, my questions:

- Has anyone built this before...

• fydo
• Replies: 3
• Forum: Troubleshooting

This is the thread that raised my question in the first place since it makes the AionFX versions the opposite of the original pedals and every other clone. My question is not resolved in that thread and still hasn't still hasn’t been answered.

hey look! verification of what I just posted. might as well get flagged for unsportsmanlike conduct since football is back ...

the six connections between the rotary board and main board in no particular order ...
one has continuity to ground (pole c)
one has continuity to the middle lug of the tone pot (throws A1-3)
one has continuity to D2 (pole B)
one has continuity to C11(pole A)
one has continuity to C9 (throws B1-2)
one has continuity to R8 (throw C1)

It's like they included a schematic for a reason.

I must be phrasing my questions poorly. I'll give it another shot. What I cannot reconcile is which detent of the rotary switch corresponds to throw ABC1 as labeled on the schematic. It could be full-CCW or it could be full-CW. The rotary datasheet doesn't list which rotary positions correspond to which holes (1-12) on the switch and the build docs don’t confirm one way or the other. Knowing the six header connections and the pole wiring doesn't resolve the issue either. I've asked the manufacturer of the PCB, read every build report and thread on this forum that mentions either of these pedals, reached out to builders via PM, and there is still no clear answer on this issue. I appreciate that you've spent some time on this, but this doesn't seem like a question that can be answered by someone who isn't @aion or who doesn't have the rotary switch to test for continutity.

 

[anevilspar7an]

@apierz
Do you have the pcb on hand?

 

[jessenator]

To ICT's point, maybe the conversation could be moved to a project-specific troubleshooting thread instead of this general one.

 

[anevilspar7an]

@jessenator
Excellent suggestion.

 

[ICTRock]

awww we're deleting posts now.

 

[GAStan]

@apierz I'm pretty sure I just received one of these 4P3T switches from Tayda in my last shipment. I'll check tomorrow and if so, ohm it out and post the results.

 

[apierz]

@apierz I'm pretty sure I just received one of these 4P3T switches from Tayda in my last shipment. I'll check tomorrow and if so, ohm it out and post the results.

That would be greatly appreciated.

 

[Aentons]

it's going to be super relevant since the needed switch is a 3P4T

let's end the day on this. there's only four throws which means that the switch only has four positions. if you've been told that cheese mode is position 1 and you've been told that position 4 is off and that the rotation is clockwise then there's nothing more to figure out here.

I think they are trying to verify that clockwise counts up and not down

 

[falco_femoralis]

I'm designing the artwork, but I can't get a clear answer on which direction the 4 modes on the rotary switches are ordered. I've asked Aion but haven't heard back and there doesn't seem to be a clear answer among the build reports and forums posts. Can anyone whose built these circuits confirm if this is the right order or if I need to reverse my labels?

hehehe

 

[Robert]

awww we're deleting posts now.

Being "nice" obviously isn't a forum requirement, but trolling the "No question is a stupid question" thread ain't right.

 

[GAStan]

That would be greatly appreciated.

I was mistaken, I actually ordered the 3P4T switch.



As viewed from the top,

fully CCW connects A to 1. Fully CW connects A to 4.

 

[Matopotato]

Yes, a DMM in continuity mode should show the positions.
A-1, B-1, C-1 connected when full CCW as seen from above facing the stem as in the last picture just above.
Next hack towards CW connects A-2, B-2 and C-2
And so on.
You can also make a continuity check with the schematic and the pcb to sort of verify the schematic.
The 1-6 on the daughterboard and the pcb should match, but you can do a continuity check as well to verify which of the 1-6 goes to A-C,1-4 respectively, but hopefully not needed if Aion did their pcb correct.
It is actually a good exercise and I find the continuity/beep of DMM to be my best friend when deciphering PCBs and build.
Still I do have pedals where the decal does not match the switches or pots ...

 

[apierz]

I was mistaken, I actually ordered the 3P4T switch.

Ah dang . I bit the bullet and ordered two of the 3p4t rotary switches from stomp box parts. I'll solder them in and continuity test when they arrive. Thanks all.

 

[Matopotato]

Ah dang . I bit the bullet and ordered two of the 3p4t rotary switches from stomp box parts. I'll solder them in and continuity test when they arrive. Thanks all.

You can do a lot of continuity testing before you get them though.
Map out where 1-6 go and get aquainted with the schematic-pcb interaction.

 

[apierz]

You can do a lot of continuity testing before you get them though.
Map out where 1-6 go and get aquainted with the schematic-pcb interaction.

Yeah, I think I have a good handle on the six daughter board connections. I'll do the same for the Obelisk and probably try to put all the stuff from my notes in a build report when it's all buttoned up. The black box is Aion's schematic labeling. There's evidence that schematic ABC1 is full-CW on the rotary (that would match the original pedal and the 1,2,3,4 labeling on the picture of his demo build), and evidence that ABC1 is full-CCW (troubleshooting reports and best guesses from the rotary data sheet).

 

[Matopotato]

A1 should be full CCW and A4 should be full CW as seen from above looking at the shaft.
Does the A or the 1 when full CCW go to one of 1-6 on the daughterboard?
If so, the same number but on the PCB should either go to C11 cap or Tone pot pin 2?
If you are able to map 1-6 to letter/number on the 3P4T daughterboard then that ought to help. I think.
(I am nearing where I would need the physical parts in front of me though)
I am thinking 1-6 should be possible to map to R8, C9, R19/R20 Tonepin 2, C11, ground or R19/C8/R10/D2/Q3. But that is 7 so not sure without a board at hand....
Not sure I am helping any...

Edit: You can temporarily loosely jumper A and 1, just to see what connects where. That would mimic the 3P4T in full CCW position.
Not sure what is "Off, 1, 2, or cheese", but doc says Off is Tone bypass, and my guess that is A4 (along with B4 and C4 of course).
So from pure theory perspective I would guess Full CW is Off, and then the go in order to cheese in ABC1 position...
Makes sense perhaps when Cheese is using the trimmer and only position when trimmer is connected is C1, which would support the idea that fully CCW is cheese. And I would be quite surprised if modes "1" and "2" came out of order...

 

[Gordo]

I was in a shit mood yesterday but I still was kinda taken back by the exchange. Oh well.

 

[apierz]

The rotary switches arrived today so I soldered one in and found out my original question, "is my order correct or should it be reversed?" was based on the faulty assumption that AionFX would kept the order of the modes the same as the original pedal because that's how they are listed in the build docs ("Off (tone bypass), 1 (scooped mids), 2 (flat mids), and “Cheese” mode").

While waiting for the rotary switch to arrive I mapped out the header pins:

Header	Net
H1	C9
H2	C Common
H3	C11 (tone / recovery side)
H4	Tone pot wiper
H5	Ground (pad A)
H6	R8 / rotary hole 1

Once the rotary switch arrived, I was able to verify that the Alpha SR2612F 3P4T rotary switch connects like this (with the rotation stabilizer pin at 6 o'clock):

	Full CCW outer pins	1 click CW outer pins	2 clicks CW outer pins	3 clicks CW (Full CW) op
12 o'clock common	5:30	4:30	3:30	2:30
4 o'clock common	1:30	12:30	11:30	10:30
8 o'clock common	9:30	8:30	7:30	6:30

With the rotary in place, Full CCW had continuity across H5 and H6. Since H6 goes to R8 that means Full CCW sends the trim pot to ground and is "Cheese Mode." Full CW had continuity across H3 and R19 and R20, so that is the "Off" mode. The other two were trickier because I don't think the schematic updated the MODE._ labels, but the silk on the PCB did. MODE.C on schematic is A on the daughter board. MODE.B is C and MODE.A is B. It's a real Street Fighter boss situation. With that sorted I verified that C on the daughter board had continuity with C9 on 1 click CW. Assuming this cap is causing the mid scoop, that's "Scooped Mids" mode found. Verifying 2 clicks CW was flat mids done by finding no continuity no that click between C and C9.

So if I understand C9 correctly, the order is:

Click	Mode
Full CCW	Cheese
1 click CW	Scooped Mids (1)
2 clicks CW	Flat Mids (2)
Full CW	Off

and the answer to my question is, "Neither."