Aion Fx Theseus issues - King of tone

[eurobailey]

I built the aion fx KOT about 4 years ago and its been the bane of my pedal building journey!!!

The first time my issue was a solder bridge on the switch. Once fixed, the pedal worked however on side B i get the boost and drive settings but not the distortion setting. On Side A i get all three settings working as they should.

My tests so far have been checking FV of the diodes in circuit (no power) to ground and they seem ok. The hard clipping diodes are 1n914 in my build.

I have also checked continuity between the diodes and the switch. So i get continuity with the switch UP or DOWN with the respective diodes.. which seems incorrect however i get this on Side A and B and have no issues with Side A?

i am assuming i have a faulty switch or a solder bridge somewhere but i am a bit stumped as what my next move should be? Would love any suggetions.

Today I unsuccessfully tried to remove the dip switch… I will try again tomorrow but also wondering what else I can try to get this to work ? Someone suggested running a wire on both sides of the “hard clipping “ switch to permanently have the diodes in the circuit but this didn’t seem to have any impact.

I am using Revision A from aion FX. This is the schematic.

https://aionfx.com/app/files/docs/theseus_documentation_v1.pdf

 

[szukalski]

I can't see anything wrong from the pics you've provided..

 

[eurobailey]

I can't see anything wrong from the pics you've provided..

apologies, i havent provided photos as in this case i wasnt sure it would help. The pedal is working apart from the distortion so its not a wiring issue. I guess i am trying to track down what i can test to see if its a switch failure. I am not sure. a photo will show a damaged trace for example and often it just promotes commentary around adding more / less solder etc (not saying that is not an issue, but i am trying to understand the circuit more to be able to test areas that might reveal my issue).

 

[szukalski]

Connect the switch to GND instead of the diodes. The signal should drop out when you flick the switch. It would show the switch working.
I always found the dist to be mildly different at best.

 

[eurobailey]

Connect the switch to GND instead of the diodes. The signal should drop out when you flick the switch. It would show the switch working.
I always found the dist to be mildly different at best.

That’s a great shout thanks.

Yeah I think it’s half the reason I didn’t get this pedal ! I always expected the distortion setting to be “distorted” it’s a hair more gain. The only way I really worked it out is people said you will get a volume drop for each setting, from boost.. to drive to distortion.

 

[szukalski]

The Sheepylove Kaiser (Chuck's Emperor of Tone) has the dist blend on a pot, and there is a difference but you have to question whether it's worth the cost of a pot

Another thing to try is a boost in front. Get a bit more signal, which should distort a bit more.

 

[eurobailey]

The Sheepylove Kaiser (Chuck's Emperor of Tone) has the dist blend on a pot, and there is a difference but you have to question whether it's worth the cost of a pot

Another thing to try is a boost in front. Get a bit more signal, which should distort a bit more.

yeah my main thing thats annoying me with this build is that on side B i am getting no distortion at all. Its literally the boost setting. With the soft clip i get the over drive setting. Side A it all works. I will do what you suggested tomorrow and see how i go.

 

[eurobailey]

So, bad news i. guess! i have taken the pcb out of the enclosure and connected it up to my test pedal. Side A (that works) when i shunt the hard clip to ground with the switch up, the effect goes silent (as expected). When i do the same to Side B (that isnt working) and shunt the hard clip to ground it also goes silent....... Which means the switch is doing what it should??? The only thing that seems weird... is that for the soft clipping diodes (when i shunt them to ground, with the switch down, and i touch the top part of the switch, it goes silent as well? shouldn't it only do this when the switch is up?

yes the Switch A (looks low on solder) that had issues earlier and now rectified. The board itself looks a bit covered in flux, when i built this i was having issues with my solder iron (there was a hole in the tip! that i wasnt aware of) i could give the board another clean. If the switch is operational, what else can i do to try get those diodes in circuit to see that are working?