Polysix GND cable mod or hack.
2014-01-15 by <josh.nursing@gmail.com>
If you haven t seen the small hack I did so as not to have to unsolder and re-solder the large GND cable to KLM-367 while troubleshooting, the album is here
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Page 35 of 114 · 5658 messages matched
RE: Lots of pots not working, MG, VCF, EG.
2014-01-15 by <josh.nursing@gmail.com>
CPU Socket replacement took a very long time: it s really hard to first, remove solder and then empty the vias. I sometimes used a mechanical pencil lead to
RE: Successful mod but something else changed!?
2014-01-14 by <josh.nursing@gmail.com>
I recently had some interference when touching the Cutoff bare pot (i.e. without the knob on). Yash
RE: Lots of pots not working, MG, VCF, EG.
2014-01-14 by <josh.nursing@gmail.com>
What are the measurements at D5 and D6 in-circuit? I get values both ways in-circuit. Lifted one end of each but the diodes seem good when tested that way.
RE: Successful mod but something else changed!?
2014-01-12 by <jim@saltlands.com>
Chris, were you referring to me and my problem with strange sounds coming from knobs? I still haven t sorted this out, but this seems promising, regarding
RE: Successful mod but something else changed!?
2014-01-12 by <josh.nursing@gmail.com>
That s a very good point: I made sure that the cables are far from IC33. This little section from the service manual must be empirically important. Yash
RE: Successful mod but something else changed!?
2014-01-11 by <stannloo@yahoo.com>
Hi there, I ve been following this thread with interest... Just an idea (and it certainly could lead nowhere but it s worth a try): I saw that mention on
RE: Lots of pots not working, MG, VCF, EG.
2014-01-11 by <josh.nursing@gmail.com>
I never said IC6 sends CV, I only said it s connected to CPU s T0 through the DATA signal. Also, I didn t find any other pot than Cutoff or FX Speed which
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-11 by Bob Grieb
I sort of see what you are saying, but not sure I agree with your conclusions. Basically the DAC is used for two things. It is used with the comparator IC6
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-11 by <josh.nursing@gmail.com>
I can understand your confusion: there are several simultaneous issues and different posts in this single thread detailing all the issues, including new ones I
Re: [PolySix] Patch Sharing?
2014-01-10 by Bob Grieb
Does a std exist for PolySix .syx files? Assuming Kenton s MIDI kit and the Korg one both dump sysex, do they use the same format? Thanks, Bob
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-10 by Bob Grieb
I am confused. Why are you working on the output mux when the problem seems to be with the front panel input circuitry? The DAC calibration procedure
Output Switch issue.
2014-01-10 by <josh.nursing@gmail.com>
Not sure if it s related to the other problems with the Polysix I have, but I can only hear a proper output with the Output Switch set to Low. If I try to set
Patch Sharing?
2014-01-10 by <boom2496@yahoo.com>
Anyone interested in doing some patch sharing on here? Preferably .syx?
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-10 by <josh.nursing@gmail.com>
What could be the reason that IC18-P12 (Res) picks up the signals from all other Pots? There do not seem to be any continuity or shorts problems around IC18,
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-10 by <josh.nursing@gmail.com>
Very good advice as usual, Bob, thanks. Will do that right after the current KLM-367 INH/DATA/P2x check and I am also trying to fit a jumper/socket for the
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-09 by Bob Grieb
Josh, I would use an ohmmeter to check the resistance from IC1 4051 front panel mux pins 9,10 and 11 and also INH1 and INH2 all the way back to the
RE: Lots of pots not working, MG, VCF, EG.
2014-01-09 by <josh.nursing@gmail.com>
Meant IC18-12 instead of IC18-2 for Res.
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-09 by <josh.nursing@gmail.com>
Interesting results, Bob: at the DAC calibration step, only Effects Speed makes Leds 1 light up to 4 (in the very first values near Min), all the while LED 5
RE: Lots of pots not working, MG, VCF, EG.
2014-01-09 by <josh.nursing@gmail.com>
Here is what a Cutoff sweep from Min to Max sounds like in my Polysix for now. You will hear quite a bit of noise in the form of fluctuations in the signal. In
RE: Lots of pots not working, MG, VCF, EG.
2014-01-09 by <josh.nursing@gmail.com>
Not sure I did this correctly as I swept one knob from Min to Max, then put it back to Min, then swept the other knobs similarly for each pin, because then I
RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by <josh.nursing@gmail.com>
Johannes, many thanks, this is just the kind of information I am looking for. After the power supply recap and the KLM-366 check, I will go through this
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by <josh.nursing@gmail.com>
Sounds like a good idea, Bob, thanks. Will try that after re-capping the power supply, and doing some continuity testing on KLM-366, as the board seems to have
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by Johannes Hausensteiner
3.5V on D2 is perfectly OK, there is a 10K resistor is series and the voltage is only 5V. This leaves less than 1mA so the Zener voltage is not even reached.
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by Bob Grieb
Josh, I think LED 5 means that when the CPU is trying to select the Effects pot, its actually selecting one of the pots that is set to the middle
Re: [PolySix] Tuning Issue--the opto is replaced
2014-01-08 by <josh.nursing@gmail.com>
Well done, Michael, and thanks for sharing. One day it will be good to collect all the info about how to diagnose and repair a Polysix in one wiki or FAQ to
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by <josh.nursing@gmail.com>
Replacement Zener found and installed at D2, continuity tested around it, part of calibration procedure re-done, when calibrating the DAC, LEDs 1 & 5 are still
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by <josh.nursing@gmail.com>
Looks like I ve got a faulty Zener diode D2... In circuit, it passes through 3.5V instead of 3.9V. Tested off circuit, it s giving me Infinity with the Digital
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-08 by <josh.nursing@gmail.com>
Not what I meant: when the service manual says to put all the sound settings at normal, almost all of the pots have to be put at Min (0 on the panel). On the
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-07 by Bob Grieb
The DAC calibration uses the Effects Intensity, not the EG intensity. Are you using the wrong pot? Bob ________________________________ From:
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-07 by <josh.nursing@gmail.com>
When re-doing the calibration, at the DAC level, I still get only LEDs 1 & 5 On, and no amount of variation of VR6 and VR7 changes a thing, so I still also
RE: Lots of pots not working, MG, VCF, EG.
2014-01-07 by <josh.nursing@gmail.com>
Spent some more time with the control boards: socketed the 4501 so that I can swap more easily. Tested with the new 4501 and it does look like I get control
Re: [PolySix] Tuning Issue--the opto is replaced
2014-01-07 by <mzaec@mail.ru>
Hi everyone! I ve read this forum and I see that people have the same problem with PolySix as mine. It turned out that the problem is not in opto. What helped,
RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
That rings a bell, Bob: I can see Malte also once wrote to me saying the signals are multiplexed and passed through CN11, and that there could be a
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
Maybe you have a bad 4051 on the front panel board? If some pots interfere with other pots, then somehow the muxing is not completely working. Are all
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
Ok, will leave P1 of my DAC as is. Good progress for today, so thanks a lot, Bob. Yash
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
Did a few things (see below the soundcloud link) and here is what it sounds like (it does sound like a Polysix should sound to me judging from Youtube videos
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
The data sheet for the DAC lists pin 1 as a no connect, so I don t think you have to connect it. Bob ________________________________ From:
RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
Made a mistake earlier referencing the two pins for IC 33 (the DAC), because of course, if you re looking at the board from below.... So, on the clone boards,
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
Josh, One thing to keep in mind- the CPU chip has code in it, so you can t simply buy a new one. Be careful when probing anything that connects
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
Not sure why my text is always bold. Silly Yahoo mail program. In most cases, we would assume that the pc bd is good, and just check the components.
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
You bet! Going to find if I can get one. There does seem to be some funny things happening around CPU-P1, R72, D10 and even D11 (both ends of the latter are
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
Working without a scope certainly makes it tougher. ________________________________ From: josh.nursing@gmail.com To:
RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
IC27-P1: stuck on 3.88V in Manual mode, stuck on 0.88V when in normal mode.
RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
All right, I m going to check these., the list is fine as the mails are opt-in, and if it helps somebody else, it will be good. Not sure I am ever going to get
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
Check the 4.7K pullup resistor and the diodes and resistors around the comparator. Maybe something is not connected on the pcb. The logic probe could
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by Bob Grieb
Hi Josh, Maybe we should take this off-line so that others don t have to get all of the emails? If you want, you can email me at rlgrieb then the
RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
Funny, I used the logic probe on CPU pin 1, and suddenly I get control over Cutoff, Res and EG Intensity (but it s flaky, as sometimes it happens). Nothing
RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
Starting with all pots at Center position, I do get 0V on the data pin. All pots to Min: I get -4.35V All pots to Max, I get 4.35V. Since Res is the only pot
Re: [PolySix] RE: Lots of pots not working, MG, VCF, EG.
2014-01-06 by <josh.nursing@gmail.com>
IC33-P8