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Subject: Re: [PolySix] some defects after battery leak

From: Johan De Vroede <johandevroede@yahoo.com>
Date: 2015-05-15

I also think it's a good idea to load the factory patches. So I can exclude the controls... I found my original Korg data cassette and I tried to load the data but it didn't work. ( I heard sound in my headphone when playing the tape ) Then I downloaded the wav file from internet and took my portable but i am not able to load the data. It's not working. I have the procedure how to load the data. I measure 200 mV ac signal ( I don't have an oscilloscope ) on the data connector but there is no data loaded ( the found and loading leds don't light when I play the wav file )
Damned !
I am slowly loosing my optimism.





Sent from Yahoo Mail for iPad

At 15-mei-2015 15:58:02, backshall1@bellsouth.net [PolySix]<'PolySix@yahoogroups.com'> wrote:














I like Bob’s suggestion. If you load the factory presets and try a bunch of
them without turning any knobs and they sound correct, then the D/A converter is
probably okay. I don’t know how familiar you are with the factory sounds, but if
they sound reasonable and are not “growling” then they are probably okay. In
this case, it could be a MUX problem. There are four 4051
multiplexer/demultiplexer chips (14051 is the Toshiba number). There are two
used as multiplexers on the panel boards and two used as demultiplexers on the
KLM-367 board.


-IC1 on the KLM-370 is the multiplexer for Effects speed, Filter and
Envelope Generator settings, and Keyboard tracking.

-IC2 on the KLM-369 is the multiplexer for PWM and EG (LFO) controls, but
you haven’t mentioned any problems with those.

-IC18 on the KLM-367 is the Demultiplexer for Effects, Filter, EG, Kbd
Tracking.

-IC19 on the KLM-367 is the Demultiplexer for PWM and EG.


There are a bunch of control lines to check here:

-P20, P21, P22 on processor IC22 pins 21, 22, 23 going to each of the four
chips pin 11, 10, 9.

-Two Inhibit signals from IC23 pins 1 and 3. The INH1 (IC23 pin 1) is
connected to IC 1 on KLM-370 pin 6 and INH2 goes from IC23 pin 3 up to panel
board KLM-369 IC2 pin 6.

- Two Inhibit signals from IC23 pins 4 and 10, to IC18 pin 6 and IC19 pin 6
respectively.


If you have a dual trace oscilloscope, you should see that the pairs of
inhibit signals are opposites of each other. When INH1 is high, INH2 should be
low, and vice-versa.


Don B.






Sent: Friday, May 15, 2015 9:06 AM


Subject: Re: [PolySix] some defects after battery
leak






The
only fault is the growling sound and the VCF that acts as an EG. All leds
are functioning as they should. When I switch on the PS6 bank A en 1 are
lid and then I put it in manual mode so the light from 1 goes out .
The
corresponding lights for buttons A to D and numbers1 to 8 work when
selected. When I put the VCA in EG mode and turn sustain to 0 there is no
sound, thats normal, but when I then turn the resonance knob above 3 the
sound comes up smoothly and increases in level ( it's difficult to
explain, you should see it ) Resonance doesn't work at all as it should :
it varies the sound but there is no " high resonance " sound when turning
it high ( and turning cut off towards zero ) the only thing that you hear
is the sound becoming growling. Same with turning cut off, eg intensity,
kbd track beneath 3 or above 7 and also when increasing the intensity for
phaser and ensemble.... Very strange . All other things work : tune, bend,
VCO ,MG , EG and VCA , arpeggio and key assign .




Sent from Yahoo Mail for
iPad



At 15-mei-2015 14:08:11,
backshall1@bellsouth.net [PolySix]PolySix@yahoogroups.com'>
wrote:





















You are correct about IC24 being marked incorrectly on the
schematic as
IC34. It shows two chips marked IC34, but the one
beside IC30 should be IC24. I
have that written on my paper copy of
the schematics. Here is the list I have of
schematic errors for the
KLM-367.




1) On IC30 and IC31, pin 5 in connected to +5v, not pin 4.




2) IC30 ground pin is pin 7, not pin 1.




3) The 14042 chip below IC26 is IC24, not IC34.




4) The capacitor connected between R28 and pin 6 of IC3 is C5, not

C4.




5) The diode on pin 9 of IC29 is D13, not D12.




6) The diode on pin 15 of IC29 is D14, not D13.




7) The signal from pin 7 of IC14 is MG Level, not MG Speed.




8) Capacitor C33 is connected to the collector of Q5, not the other
side of
R98.




9) The LM339 quad comparator is IC2, not IC3.




Are there any other symptoms besides the growling sound, maybe
lights
turning on when they shouldn’t on the A-D or 0-9 patch
buttons? Any other
buttons not working properly? It sounds like it
could be a D/A converter
calibration problem.




Don B.













Sent: Friday, May 15, 2015 6:35 AM




Subject: Re: [PolySix] some defects after battery

leak













I tested all sugested data lines and
they all
are okay. One remark : datalines D04-D07 have to be tested
to
IC30, IC24, IC33, IC29,
IC35) and not IC34; there is a faulty diagram of
KLM367 on the
internet .


The
problem
still persists. I doublecheked the powersupply and all
voltages are okay. So
does anyone here have another suggestion? I
think it's mainly the VCF that
causes all the problems. turning cut
off, resonance or KBD track changes the
sound from good into a
growling sound. Also the ensemle gives growling sounds
when turning
phase or ensemle too low or too high.






regards and thanks in

advance











From: "backshall1@bellsouth.net [PolySix]"
PolySix@yahoogroups.com>
To: PolySix@yahoogroups.com
Sent: Thursday, May 14, 2015 6:38
PM
Subject: Re: [PolySix] some defects
after
battery leak






















Most of the damage is usually on
the
eight data lines (D00-D07) and that includes IC30 as well as
IC31. The best way
to test these is to use the ohm meter to test
continuity from one starting point
to all the other places these
lines are connected. From a suggestion from Andy
Jury a long time
ago, I usually test from connector CN10 to all the other chips.
This
can be a bit tedious. D00 is pin 4 on CN10, and needs to be tested to
IC31,
IC26, IC33, IC28, IC34, then do the same set of tests for the
other seven data
lines on CN10. Alternatively, you could start from
IC31 pin 6 and test
continuity to IC26, CN10, IC33, IC28, IC34. When
you get to D04-D07, it will be
a different set of chips (IC30, IC34,
CN10, IC29, IC35).




Don Backshall


















Sent: Thursday, May 14,
2015
12:13 PM




Subject: Re: [PolySix] some
defects after
battery leak
















Thanks

for the reply. I repaired traces that were broken and I
checked if there
was continuity between traces that should not
be connected to each other.
I did this only for IC 31 maybe I
will take a wider aerea to check on
continuity. The weird
thing is that most things work as they should and
then when
you turn one knob several parameters are changed and not only

the one you turn. I put it in manual mode so all knobs
function as they
are set and then I can get some rather good
sound but for example when I
then turn the resonance of the
VCF a bit then other parameters seem to
have changed....any
other info? I replaced the IC31 and put it on a
socket. Could
it be that another IC is defective when I have this strange

behavior or do you think this is mostly a result of the
corrosion?

Thanks again for the reply









At 14-mei-2015
17:13:41,
'Chromatest J. Pantsmaker' chromatest@azburners.org

[PolySix]PolySix@yahoogroups.com'>

wrote:





















There are two things (well,
more
than that actually) that the corrosion will do that we
need to pay
attention to.




First is the broken trace,
or lack
of continuity. You've checked this with your meter.


Second is the shorted trace, or
too much continuity. By this
I mean that a trace can have
continuity to a trace next to it. That
would cause the
signals to affect each other. When you check continuity
on
the traces, it's important to not only check 1-1, 2-2, 3-3 (and
so
on) but also to check 1-2, 1-3, 2-3 (and so on) You want
all of the 1-1,
2-2, 3-3 traces to have continuity, and you
∗DON'T∗ want the 1-2, 1-3,
2-3 traces to have continuity
unless they are actually connected via the
schematic.