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 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 | |