AION DEIMOS (Tone Bender) Help

[mattc]

It's just not been a good couple of weeks with the builds (though I built a BB Pre last week that did fire up on the first try).

I built the Deimos, which is a clone of the Tone Bender Mk. 2.

Here's where I am:

- In bypass I get signal, with the effect on, nothing.   
- I did a signal trace (using the TH Custom pen, which is great), and I'm getting signal on the base of all three transistors.
- Pin 5 of the IC is putting out -8.89 v
- Q1: C = 0, B = -2.65, E = 0.1
- Q2: C = -1.75, B = 0, E = 0
- Q3: C = -1.95, B = 0, E = -0.772

The only deviation from the build do is to use a 1kB instead of a 1kC for the Fuzz.

[mattc]

Pictures

[harryklippton]

Did you check continuity between the main board and the bypass board? Sounds like the main board is getting power but is it getting signal in and out?

[Zerro]

Those collector voltages at O1 and O2 are too low.
See this link:
https://aionfx.com/app/files/docs/deimos_legacy_documentation.pdf

Something is wrong at Basis of Q1 and Q2. Too much opened C-E passes, or voltages aren't going to Colectors. Control resistors around Basis and Colectors. And transistors too.

I attached 2 pro-versions. See for experiments!

For bettter Q1 opening, try to lower Resistor 1M5 in Basis at cca 680kOhm, so to get cca -4,5V at Colector. The same voltage I would set at Q3 too! Try to set it and compare sounds. Maybe you will like it, maybe not.

[Caedarn]

Your trim pots in the picture look like they're fully CCW. Is this the position they were in when you took the voltage? Would expect them to be closer to 12:00

[Zerro]

And some soldered points at photo of PCB seem to be defect or shortened with ground by tin dirt. Use needle and clear space around of all points at both sides of PCB. Use sufficient amount of rosin and tin.

[mattc]

Thanks all.  I'll give those suggestions a try and report back.