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

From: Johan De Vroede <johandevroede@yahoo.com>
Date: 2015-05-16

Yes, both switches are on and the led " tape enable " is lid. Then I push button " from tape " and the led lights up. I load the data but the " found " and " loading " led don't come up. I tried severall output volumes. I also tried the " verify " procedure but the " error " led doesn't come up when I increase the output volume. I will ceck the KLM 367 again to see if all traces are okay....

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At 15-mei-2015 22:32:19, backshall1@bellsouth.net [PolySix]<'PolySix@yahoogroups.com'> wrote:














Tape Enable and Write Enable switches are both on? I don’t know what the
signal level should be.






Sent: Friday, May 15, 2015 1:14 PM


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






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.