Hi Paul,
Before you do anything else make sure that pin 1 of IC7 swings between -5v
and +5v (or thereabouts) as you turn the EG knob clockwise.
Cheers,
Andy
From:
PolySix@yahoogroups.com [mailto:
PolySix@yahoogroups.com] On Behalf Of
Paul
Sent: 11 November 2009 00:02
To:
PolySix@yahoogroups.comSubject: [PolySix] A few questions about my new Poly-six
Hello,
I have recently acquired a Korg Polysix and am now in the process of fixing
it up.
Luckily the battery problem was already done by the previous owner, all the
broken traces were replaced with wires and a new battery was fitted.
The synth plays alright, I already took apart the key contacts and cleaned
them but will have to go back and do it again because a few keys still dont
work all the time.
I also have to replace 13 of the 19 push buttons for patches and tape
memory, I have already ordered those.
My question is about calibration. Ive tuned a much simpler Roland JX-8P in
the past, which only had a few very simple variable resistors and took a few
minutes. Ive Looked over the calibration procedure for this synth and it
seems much harder.
The reason I want to do the calibration in the first place is because Ive
noticed that a few of the functions on the synth dont work correctly.
The EG intensity knob doesnt change the sound at all, while all 4 EG knobs
(ADSR) work in a way that I believe is wrong. I was going to describe it
here but gave up as they just seem really random. I think the best way for
me to describe them would be to make a video, which I will do later.
Ive tested all the 10k pots on that board with a multimeter and they seems
to all function the same: They start at 1.09k when they are all the way to
one end and move up to about 2.9k somewhere in the middle and then back down
to 0 on the other side of rotation.
I should also mention that ive loaded a bank of stock presets and they dont
seem to function correct either. I had to turn the ADSR knobs to random
positions it seems to get any sound out of the few patches I tried.
I did notice that there are adjustments listed for all the different EG
functions in the instructions. Could I just skip to those tests or should I
follow the full guide step by step?
I have a multimeter and a PC oscilloscope. Ive also made the 56k Ohm jumper
that is talked about in the calibration instructions.
Ill make a video of the problem and post it on youtube later tonight or
tomorrow.
Any help would be much appreciated!
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