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Discussion about the Korg PolySix synthesizer

Index last updated: 2026-04-28 23:40 UTC

Message

Re: [PolySix] some defects after battery leak

2015-05-15 by <backshall1@bellsouth.net>

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

From: mailto:PolySix@yahoogroups.com 
Sent: Friday, May 15, 2015 1:14 PM
To: PolySix@yahoogroups.com 
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.





        From: mailto:PolySix@yahoogroups.com 

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

        To: PolySix@yahoogroups.com 

        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.











                From: mailto:PolySix@yahoogroups.com 



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


                To: PolySix@yahoogroups.com 



                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

















                From: mailto:PolySix@yahoogroups.com 




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


                To: PolySix@yahoogroups.com 



                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 





                      Johan



                      Sent from Yahoo Mail for 
                      iPad






                        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.

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