Aion Andromeda kit troubleshooting help needed

[Paul D]

Hello, newbie here and this is my first build in years. I built the Aion Andromeda latest version kit using the documentation here: https://aionfx.com/app/files/docs/andromeda_kit_documentation.pdf

I followed the instructions closely, no part substitutions.  There is one recent change where the documentation is behind but confirmed by email, a 10k resistor instead of 4k7 for the LEDR spot. 

LED lights when on, pedal passes sound when off, but there is no sound when on. Battery measures 9.58V but there are no voltage readings on any of the IC pins with boards installed and probe grounded to the box.

I've looked for bad solder joints or bridges but can't see anything obvious.  I also slightly melted the corner of one of the film caps when soldering one of the pots to the main board, but I'm not sure if that damage would affect function.  Not sure what to do next, any help is appreciated!

[duck_arse]

welcome to the forum. also:

Battery measures 9.58V but there are no voltage readings on any of the IC pins with boards installed and probe grounded to the box.

No, sir! we don't allow this. the only time there are no voltage readings is when the voltmeter is switched off. please, measure the voltage on each pin, and list what the meter indicates. for all pins. of all IC's. find ground on your main board and do the measures from there.

are you using only battery, or have you tried with external supply as well? and the melted cap - the outer plastic jacket is the "box" part of boxcap, inside will be an epoxy coated cap which will remain untroubled by the melting. generally, unless very lesser quality caps.

[Paul D]

welcome to the forum. also:

Battery measures 9.58V but there are no voltage readings on any of the IC pins with boards installed and probe grounded to the box.

No, sir! we don't allow this. the only time there are no voltage readings is when the voltmeter is switched off. please, measure the voltage on each pin, and list what the meter indicates. for all pins. of all IC's. find ground on your main board and do the measures from there.

are you using only battery, or have you tried with external supply as well? and the melted cap - the outer plastic jacket is the "box" part of boxcap, inside will be an epoxy coated cap which will remain untroubled by the melting. generally, unless very lesser quality caps.

Thanks for the reply.  Turns out there was no power getting to the main board b/c I damaged a V+ trace on the footswitch board trying to remove an incorrect diode.   I bypassed the damaged trace and got voltage on the IC pins and some extremely distorted noise out of the pedal.  Waiting to hear back from Aion about getting a replacement footswitch board and trying again, will delete this thread or update as appropriate...

[Paul D]

Ok so I got a replacement footswitch board and got the pedal somewhat working but still having issues!  The sound from the pedal is like a high gain gated fuzz (supposed to be mid-gain natural OD) and the notes die out after a couple seconds. With drive level higher than minimum there are lots of clicks/pop noises like a heartbeat. Plenty of level available but hard to tell if tone controls are doing much.  Same results with battery or isolated power supply.  Happy to take any additional measurements that may be needed. Thanks in advance for any help!

IC 1 pin readings -
Pin 1 - 4.25v
Pin 2 - 4.25v
Pin 3 - 4.25v
Pin 4 - 0.0v
Pin 5 - 4.19
Pin 6 - 4.25
Pin 7 - 4.25
Pin 8 - 8.52

IC 2 pin readings -
Pin 1 - 7.92v
Pin 2 - 4.24v
Pin 3 - 4.18v
Pin 4 - 0.0v
Pin 5 - 7.91v
Pin 6 - 7.90v
Pin 7 - 7.92v
Pin 8 - 8.52v

Edit: pin layout corrected, sorry!! Total newbie here...

[FiveseveN]

IC pins are numbered counterclockwise:



IC2A seems to be latching up. Can you measure (with power disconnected) the resistance between pins 1&2 and 2&3 to make sure the associated resistors and tone pot are connected correctly? Do you have another op amp to swap it with?

[Paul D]

IC pins are numbered counterclockwise:



IC2A seems to be latching up. Can you measure (with power disconnected) the resistance between pins 1&2 and 2&3 to make sure the associated resistors and tone pot are connected correctly? Do you have another op amp to swap it with?

Ah crap I'm sorry, fixed in post.  Resistance between pins 1&2 on IC2 is 18.92M and between pins 2&3 is 29.5K. Between pins 3&4 it's 47.7K.

I don't have another opamp on hand but I can get one locally if that would help. 

[antonis]

Resistance between pins 1 & 2 on IC2 is 18.92M

    

[Paul D]

Resistance between pins 1 & 2 on IC2 is 18.92M

    

What does that mean? Here's the reading, it jumps around a bit...

[antonis]

[FiveseveN]

Yup, that'll do it.
It means R20 is not making contact. Check the traces and the pads, reflow as needed etc.

[Paul D]

Yup, that'll do it.
It means R20 is not making contact. Check the traces and the pads, reflow as needed etc.

Thank you. Looks like the trace runs from Pin 1 > R20 > C14 on the front of the board and from R20 > C14 > R17 > R19 > pin 2 on the back. Best I can tell there seems to be an issue between C14 and R17. I reflowed all the solder on all those components.

FWIW, Pin 1 > left side of R20 = 0.0 ohms, Pin 1 > right side of R20 is 20k. Pin 1 to left side of C14 is 0.0, Pin 1 > right side of C14 is 20k. Pin 2 back to left side of R17 = 0.0, Pin 2 > right side of R17 = 1.2k. All that makes sense I think? But C14 to either side of R17 is roughly 18.6M, though sometimes to get a reading I have to switch the range from 20M to 200M and then it only reads 1.2M which seems strange.     

I clearly have no clue what I'm doing so any help is much appreciated!

[antonis]

Best I can tell there seems to be an issue between C14 and R17..

No issue at all..

Resistance measurement via DMM is accomplished with the use of DC..
(known costant current through the resistor and measured voltage drop across it..)
Caps block DC, so no effective measurement..
(those "resistance" fluctuations are due to capacitor charging state -  an empty cap should initially show almost zero resistance..)

[FiveseveN]

Pin 1 > left side of R20 = 0.0 ohms, Pin 1 > right side of R20 is 20k

What about Pin 2 > right side of R20? Should also be a short (0 Ω).

I clearly have no clue what I'm doing

Well that's the caveat when building from kits. What happens when something goes wrong?

[Paul D]

Best I can tell there seems to be an issue between C14 and R17..

No issue at all..

Resistance measurement via DMM is accomplished with the use of DC..
(known costant current through the resistor and measured voltage drop across it..)
Caps block DC, so no effective measurement..
(those "resistance" fluctuations are due to capacitor charging state -  an empty cap should initially show almost zero resistance..)

That makes sense, thanks...this was on the back of the board, between the legs of the two components following the trace.  Would that make a difference? Seems like there should not be so much resistance there.  The trace appears to be OK, and I get a reading from Pin 2 to both sides of R17 so I think the pads are OK. 

[Paul D]

Pin 1 > left side of R20 = 0.0 ohms, Pin 1 > right side of R20 is 20k

What about Pin 2 > right side of R20? Should also be a short (0 Ω).

Pin 2 > right side of R20 is also reading ~19M. 

I clearly have no clue what I'm doing

Well that's the caveat when building from kits. What happens when something goes wrong?

Yeah lesson learned! I thought I'd save a few bucks and try a cool OD. At this point with the replacement board/parts I've spent as much as a new Nobels and way more time than I expected, and still don't have a working pedal.  It was fun and educational though, just wish I could actually have something to show for it! Might be time to cut my losses...

Anyway I really do appreciate the time and effort to help me.  I didn't realize that Aion had no real tech support when I bought it.  It is a good kit, great documentation and all the parts were there, I'm just sloppy and clumsy so probably bridged a trace or damaged a pad somewhere or something. I'm better at guitar than I am at soldering lol.   

[FiveseveN]

Don't give up yet, you're nearly there.

Pin 2 > right side of R20 is also reading ~19M.

That's virtually open, which is the opposite of what it should be. Solder a wire between these two pads to bypass the apparently interrupted trace.

[Paul D]

Don't give up yet, you're nearly there.

Pin 2 > right side of R20 is also reading ~19M.

That's virtually open, which is the opposite of what it should be. Solder a wire between these two pads to bypass the apparently interrupted trace.

Thanks, I can try that...do you mean between C14 and R17, or between R20 and Pin 2?

[FiveseveN]

R20 (right side) and Pin 2

[Paul D]

R20 (right side) and Pin 2

Ok great thank you I'll try that and see what happens!

[duck_arse]

Anyway I really do appreciate the time and effort to help me.  I didn't realize that Aion had no real tech support when I bought it.  It is a good kit, great documentation and all the parts were there, .....

we get a lot of questions here, about a lot of companies making kits, like Aion. but he actually does come in here now and then, and will help where he can with any problems. not like stew whatsis.