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I've made a mess - Printable Version

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I've made a mess - piotr - 11-08-2022

Hi everyone,
Today, after putting my FX Kit back to the wooden case (changing jumpers) and accidentally plugged 12V adapter my FX Kit is partly broken.
The audio circuit (INPUT via GAIN to MASTER) works fine, but the 'digital' part of the FX does not respond. No lights, no sequence/envelope, no looper/shifter, etc.
Is there any way to try to reset it? I know, I know... this 12V is total FCKP. Too many wires on the desk :/ 
Please let me know about any check-out or recovery procedure I should perform to find out what I've actually done.
Greetings,
Piotr

RE: I've made a mess - Quolcat - 11-08-2022

Hello Piotr

There is not a real way to reset it;

If you can tell us more info about the power supply you used we can make a better idea of the problem, cause 12V should not damage in that way the module. We think that probably you used an inverted power supply.

I would suggest you to try to put it back in the eurorack to see if it still works in there.

Wait for your updateee :)

RE: I've made a mess - piotr - 11-10-2022

(11-08-2022, 03:48 PM)9bar Wrote: Hello Piotr

There is not a real way to reset it;

If you can tell us more info about the power supply you used we can make a better idea of the problem, cause 12V should not damage in that way the module. We think that probably you used an inverted power supply.

I would suggest you to try to put it back in the eurorack to see if it still works in there.

Wait for your updateee  :)



Hi there, thanks for your reply.
So, we've got two discoveries.

First, I've checked both adapters possibly plugged in to FX KIT. One is ~12,3V, the other one ~15,5V, even if the label says 12V (ugh, great...). One of those two was plugged in.

Second, I've found this on the lower board (images below).

No working: looper/shifter, CV interface, CV generator ( + no lights at all)
Mixer, delay and reverb works fine. Of course, it's impossible to control CV input routing to selected parameters (selecting diode color).

FX was bought used, but worked fine. I don't know if this scratch on the lower board was caused be me.

So, we have 3 possible reasons:
1. 12V "+" in center
2. 15V "+" in center
3. Physical board damage

An analogue 'half' of the FX KIT still works (wow!).



[Image: 1cf88597-4382-41dc-bb4b-db12cb9d820f.jpeg]

[Image: fdccfc66-d350-41ea-87f6-7edadc31348e.jpeg]

RE: I've made a mess - chrisi - 11-10-2022

Thanks for sharing that info. Negative (center positive in that case) voltage is bad for the Field Kit FX, so most likely your internal power supply is now damaged. Again, you could verify this by trying it out in your modular case - I expect it to still work.

If you look at the bottom board - top side with all the components - very close to the left of the DC input jack you might be able to spot a tiny, damaged IC with 5 legs.

And that small portion that was cut out of the board was done by us. There was an error in the production files of this Field Kit FX batch and the location which has some copper cut out, there was a connection that shouldn't have been there. Doesn't look great but was necessary.

RE: I've made a mess - piotr - 11-16-2022

(11-10-2022, 12:49 PM)chrisi Wrote: Thanks for sharing that info. Negative (center positive in that case) voltage is bad for the Field Kit FX, so most likely your internal power supply is now damaged. Again, you could verify this by trying it out in your modular case - I expect it to still work.

If you look at the bottom board - top side with all the components - very close to the left of the DC input jack you might be able to spot a tiny, damaged IC with 5 legs.

And that small portion that was cut out of the board was done by us. There was an error in the production files of this Field Kit FX batch and the location which has some copper cut out, there was a connection that shouldn't have been there. Doesn't look great but was necessary.

Hi!
So I'm back with some photos. Is that the one IC you've mentioned? I just want to make sure that this is the one which should be checked/replaced in order to fix 9V / wooden case powering.

[Image: e1007a18-174e-4015-a594-61661337261c.jpeg]

[Image: b44c7c27-8e08-419c-b912-44006d2d9c0b.jpeg] 
I'll try 12V Eurorack powering in next days, I just need to take FIX KIT back to other location.

It will be very helpful if you could let me know exactly what part is broken (any serial numbers, producer, SKU). Is it something similar to this IC: LM27313MFX? I want to be sure i'll buy and replace the right one. 

Thanks for your help!