u/Additional_Account32

I built Marcus’s Leo last year and really enjoyed the process of it. This time I’ve had a crack at his Zo after seeing a layout on dirtbox layouts. I find the point to point layouts very enjoyable to build and this was no exception. I breadboarded a few transistors first but other than that, it’s true to the schematic on dirtbox.

It’s quite a versatile fuzz and can go from roaring fuzz to almost overdrive tones, with some glitchiness in between. As is my process with every pedal I build, I covered serve the servants by Nirvana using the pedal on both guitars and using different settings on both before basically maxing it out on the solo (2:14 if any interest).

https://youtu.be/m9aY2H4HwA0?si=SCeOzGtgXMdzwfwy

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) and they all seem fine.

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.

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

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

We are keen to rejuvenate our garage door and facade. Currently the colour scheme is a little dated and looking tired. The will be a few phases to the project from the garage, concrete possibly and then a decking area / outdoor shower that needs repair/replacement. Whilst we work in stages we need to make sure that each area ties into the other so things “match”.

For the time being I’ll just focus on the garage and front.
In regards to the garage - is the best person to spray the door, garage trims just a good painter as opposed to a builder or garage door restorer? We would also like to add some battening to above the garage door so understand a painter probably won’t do this. However is this a simple process to undertake? Is there any risks with the spraying of the door and surrounds to “not lasting” or flaking off?

Here is a photo of the current state and an ai snapshot that gave us some ideas.

So, I built this a long time ago & was never happy with it. I could coax some good sounds but regardless of how much I messed with trim pots and swapping between 9v and 24v I could never get full use of the gain pot without crazy oscillations and almost fuzz factory noise. I left it for a long time before re exploring the build this week. I was about to start again with stripboard but thought I would check out one thing first….

First time around, I never checked the gains or leakage of my transistors and put the success (or lack of) to the pcb build who have had some detractors in their quality …. With a bit more reading and some help I decided to remove the 549C npn and GE transistor. I butchered the npn whilst removing it but can assume it was well in excess of 400hfe. The GE I removed was 90 hfe but leakage was a tad high at .250.

So , I replaced the npn with a bc107 (300hfe) and the GE transistor with a Russian hfe 70 and leakage at .150. End result …. No noise, no oscillation. It goes from light overdrive to heavy distortion and I can work the whole gain range .

So far i have only tested through my computer so will try through my amp later on. I don’t think I am getting into “fuzz territory “ at full gain but i don’t think I am concerned by that.

By any chance does anyone know whether the HFE of q1 or q2 would Impact the total gain the most ? I have socketed the transistors so can always experiment more.

I am glad I came back to this one.