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12-22-2023, 09:03 PM
Hello,
My field kit fx delay has suddenly stopped working. Signal going thru isn’t delayed anymore with no feedback. Manual and Cv control of time and fdb parameters do affect sound but not as expected.
It seems like a hardware problem tho I haven’t notice anything unusual while inspecting pcb.
I tried to cleaned everything also with a contact cleaner.
No luck.
Have anyone here experienced this issu?
Any solution?
I sent an email to Koma to ask for repair but I they say they currently only support for issues under warranty…
I bought that thing more than 2 years ago… :/
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Hii :)))
Sound stupid to ask, but could be that the gain know of the Delay is not up?? Also if it doesn't looks like if the sound is going throught.
Also curious of what happens to sound when you change the parameters of it.
Anyay as you said it sound like some hardware issue, probably the delay chip have some problems and needs to be replaced.
A synthesizing hug from Berlin
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Damn, bought a second field kit fx cause it was the center of my setup.
Worked for a while and now broken again. Same.
It seems that it can’t handle eurorack level and toast.
Now I have 2 field kit rendered useless.
Can someone from KOMA at least tell us where to look at on the PCB?
Kind of disappointing…
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The delay IC is a PT2399 and is easily accessible and replaceable in the center of the lower level pcb.
You will find the IC since the code is written on it.
If you have experience with SMD desoldering/soldering, you can swap it. The IC package is Soic-16.
The IC in charge to handle signal coming in/out are TL072 and powered with +-12V, therefore they will handle Eurorack signals.
It might be though, that the delay IC is not the cause of malfunction.
You can try to fix it, I will try to assist as i can.
Otherwise drop us an email at Koma and at the moment we have availability for non-warranty repairs
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Hi PhC.
I need to understand better in order to focus the issue in a more restricted manner.
note that if the feedback control is not working, the signal might be effected and delayed anyway of a time constant but you might not notice that since it sounds the same, just delayed in time.
So please check if that is not the case by listening to the original signal and the "processed signal" side by side.
if the signals are not affected at all but still sound passes though, that means that the Delay chip is alive (but maybe not 100% working).
The potentiometers might be damaged --> TEST: Try to control the time or the feedback with CV.
Unfortunately it might be very hard to test something with the multimeter since you would need to measure points in the middle of the PCB sandwich, so i would troubleshoot for exclusion.
Maybe drop us an email and we can go on from there and exchange videos where you show us the issue in more details.