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

From: <backshall1@bellsouth.net>
Date: 2015-05-15

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.