Re: oscillator "bleed"
2018-04-05 by josh.nursing@gmail.com
I am seeing some inconsistent behaviour of the board as well. Writing from the Yahoo Group site itself.
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Group Message issues?
2018-04-05 by josh.nursing@gmail.com
I made a new Topic asking some questions about my Polysix issues and they don t appear. I replied to a post by Malte concerning C16 on the voice bard and it
Re: Polysix octave and waveform know not working
2018-04-05 by josh.nursing@gmail.com
I saw a similar thing with caps on my Polysix which indeed had KLM-267 with the battery leakage problem. I changed the caps.
Re: oscillator "bleed"
2018-04-01 by backshall1@bellsouth.net
I replied to this about 4 hours ago from my email account and it never showed up, so I m trying again directly on the Yahoo group site. All I said was I’m
Clone board C22, C23
2018-04-01 by backshall1@bellsouth.net
Has anyone verified that it is no longer necessary to change C23 from 22pF to 10pF once you have C22 properly grounded? It looks like the missing ground on C22
oscillator "bleed"
2018-03-30 by Malte Rogacki
Hi everyone; I ve observed another strange phenomenom. There seems to be some bleed directly from the oscillators into the audio output. The setup is as
RE: [PolySix] Polysix octave and waveform know not working [1 Attachment]
2018-03-25 by Hamblin, Scott
Sounds like residue from a leaky battery...? From: PolySix@yahoogroups.com [mailto:PolySix@yahoogroups.com] Sent: Sunday, 25 March 2018 1:06 AM To:
Re: Polysix octave and waveform know not working
2018-03-24 by cyclonus40k@yahoo.com
Sorry meant knobs not working. Thanks
Polysix octave and waveform know not working
2018-03-24 by cyclonus40k@yahoo.com
On klm-369, all capacitors have some greenish residue on the legs. Do you think this is cause? Thank you all
KLM366B C16
2018-03-18 by Malte Rogacki
Hi everyone; while trying to calibrate another Polysix I noticed that C16 wasn t installed on KLM366B (read: the newer voiceboard revision). Crosschecking with
New shell for P6
2018-03-15 by stephnaylor@ymail.com
Hi all, I m new to the group. Just bought a P6, pretty good condition, everything seems to be working ok. It has the Tubbtec MIDI upgrade. It definitely needs
Re: P6 MG Oddity
2018-03-05 by jimpster@me.com
Hi Florian, Replacement LM339 finally arrived but unfortunately has not solved the issue :( Any ideas? Many thanks Jim
Re: [PolySix] Effects Knob changing Waveform
2018-03-03 by <backshall1@bellsouth.net>
I don’t think it’s likely that the diodes in backwards would damage anything, just prevent them from working. The P12, P13 lines would affect how both
Effects Knob changing Waveform
2018-03-03 by notmy_realaccount@yahoo.com
I m in the process of refurbishing a polysix. There was pretty bad corrosion. All the boards were taken out, cleaned, and parts were replaced if needed. I also
Re: [PolySix] Re: P6 MG Oddity
2018-03-02 by 9-0-9
Hello Andrew, Cool, thank you for elaborating on the matching procedure, this will come in handy for fabricating the PNP/NPN replacements of this type,
Re: P6 MG Oddity
2018-03-02 by axmonti@yahoo.ca
Hi 9-0-9, I ve made plenty of replacements for the 2SA798 - just use two matched PNP transistors and place them back-to-back with their emitter tied together.
Re: [PolySix] Re: P6 MG Oddity
2018-03-02 by 9-0-9
Sorry abt that, forgot to turn html off :) I found this interesting on the subject:
Re: [PolySix] Re: P6 MG Oddity [1 Attachment]
2018-03-02 by <backshall1@bellsouth.net>
It looks like you attempted to attach a .gif image but it was blocked. I assume you are talking about the 5-pin 2SA798. This is a dual transistor which the big
Re: [PolySix] Re: P6 MG Oddity
2018-03-02 by 9-0-9
Hello everyone, Regarding to this subject, thank you all for contributing, i m also still dealing with a restored polysix having MG issues wich i will describe
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Thanks Florian, I ordered one early today when focus seemed to be on that chip. Should be here tomorrow but with the crazy snow shutting down most of the UK I
Re: P6 MG Oddity
2018-03-01 by jimpster@me.com
Thanks for your input Andy, I already swapped over the IC s you mentioned, unfortunately no difference. Hopefully I won t have to build a board from scratch to
Re: [PolySix] Re: P6 MG Oddity
2018-03-01 by <backshall1@bellsouth.net>
The leakage from MG to VCO on battery damaged boards is well known. It is usually between the board traces that go to pin 2 (VCO mod) and pin 1 (LFO output) on
Re: [PolySix] Re: P6 MG Oddity
2018-03-01 by Florian Anwander
... regardless ... Keep in mind that there is VCO modulation also via the Modwheel. Disconnect CN09 which connects the bender section with the left panelboard.
Re: P6 MG Oddity
2018-03-01 by jimpster@me.com
Hi SynthGuy, It is 100% a fault, usually the MG modulation is exclusively VCO, VCF or VCA. The only way that a working P6 would have multiple MG destinations
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
Hi ... This sound reasonable. So I d replace the LM339. Florian
Re: P6 MG Oddity
2018-03-01 by axmonti@yahoo.ca
Hi Jim, If I recall correctly, I initially had the exact same MG behaviour after I repaired the traces on my battery-damaged board. I ordered Jed s board, but
Re: P6 MG Oddity
2018-03-01 by synthguy80@gmail.com
Hi I am in the process of repairing a Polysix that has a similar issue. I lost all use of the MG section adjustment before tracing the issue to leftover damage
Re: P6 MG Oddity
2018-03-01 by jimpster@me.com
Thank you Nekoma, not bad English at all. Yes the cable socket connectors on the board do look like they were transplanted, it is something to consider.
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
0.2v on pin 1
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
Hi ... Same also at pin 1? If no, then quite likely your LM339 is partially broken. Florian
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Hi Florian, Yes, 1.6v and 1.8v constant on those socket pins with chip removed
Re: [PolySix] P6 MG Oddity
2018-03-01 by Nekoma
Hallo to everyone. Excuse my bad English. I risolve the bad MG problem just changinhìg all the motherboard connectors. and the strage transistor with 4 pin .
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
... Remove IC29 and check whether there are constant voltages at pins 11 and 12 of the socket in which IC29 would be seated. Those voltages might come from the
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Hi Don, thanks for your continued advice. I have swapped around all the the identical IC s to different sockets to eliminate a bad chip but the sound is
Re: [PolySix] P6 MG Oddity
2018-03-01 by <backshall1@bellsouth.net>
Pin 1 is VCF mod, pin 11 is VCO mod and pin 12 is VCA mod. Maybe swap chips IC 28 and 29 and see if that makes a difference? Don B. From: jimpster@me.com
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Hi Florian, Really appreciate your concise instructions. So I have got 5v when switching the MG Switch to the VCF and 0 at the other positions on IC29 at Pin
P6 power supply problem
2018-03-01 by <backshall1@bellsouth.net>
I have one P6 power supply here that is fine with no load or partial load but blows a fuse under full load. With all other boards unplugged from it, the +5,
Re: [PolySix] P6 MG Oddity
2018-03-01 by <backshall1@bellsouth.net>
In that case, hopefully the clone board has all of the chips in sockets, so it is easy to swap them around. Even if you don’t have spare chips, very few of
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
... Check the pins 1, 11, and 12 of IC29 while changing the switch positions. They should change from 0 to 5V when the switch changes its position. If No:
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Haha, if I didn t have the other P6 I would have probably assumed that the strange MG Modulation routing to Filter was the way it should be! So, I m still none
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
... Every synth technician should own a working copy of the device in repair ;-)) -- http://www.florian-anwander.de
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Hi Don, Thanks for your input. I have another fully working P6 so I swapped over the KLM 367 board from that one into the faulty P6. With this swapped board
Re: [PolySix] P6 MG Oddity
2018-03-01 by <backshall1@bellsouth.net>
Since the Mod switch and the Waveform switch depend on the P12, P13 signals from KLM-367 to the panel boards, maybe this is a connection problem on CN06 (the
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Ok thanks, I ll be aware of that when following the service manual. Just to note what you mentioned about PWM, I have indeed now noticed that MG behaves
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
... Yes I have the original, but the clone has appearently the same mismatch between printing on the pcb and labeling on the schematic. LM339 is IC2 on the pcb
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
I see, well I m working with the clone board so best to reference that. I assume you do not have the clone in your P6?
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
PS, I relate to my copy of the servicemanual, which is a scan from the original I received from Korg Germany:
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
https://sites.google.com/site/jedjorgensen/klm367a/images https://sites.google.com/site/jedjorgensen/klm367a/images
Re: [PolySix] P6 MG Oddity
2018-03-01 by Florian Anwander
... Can you send an URL to the makers wegsite?
Re: [PolySix] P6 MG Oddity
2018-03-01 by jimpster@me.com
Hi Florian, Thanks for the prompt and detailed reply. Could you check your numbers because my IC s locations and Chips don t correspond to your advice. I just