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

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

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.