POLYMOOG NOT WORKING ANY MORE HELP !!!!!!!!!!!!!!

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1

Hello everybody,

i m back now after a while as in nov. 2016 i had a stroke, sat one year in a wheel-chair and had been in a rehab

center til i got home in jan 2018. i recovered pretty well since then and i m glad to be here with my instruments

and now with all of you out there…

here is my current problem:

but now i went on to swap the burned power light on my minimoog…after screwing the half day, that thing is shining now fabulously more that ever and it sounds fantastic like before…
but as it was off the surface of my polymoog, i decided to give him (the polymoog) some well treatment, and i took all the voicecards out an cleaned them all thoroughly and put them all back, switched it on but no sound any more, except stinking burned.
i wanna add that a few years ago i got a fabulous SPSU from heimz weierhorst, and it worked perfectly since then up to now without any problems.
the only thing one can perceive is the typical hummig of the entire voices in background very low-leveled

has one of you any idea. how i can get my beautiful instrument back to life ???

b.t.w. i lost contact to my tech, heinz, completely for years now and i don t know if he s still alive, nor does know anybody else either…

cheers,
christian

2

Let me get this straight to the problem.

  1. You successfully fixed something broke. Everything works OK.
  2. You removed the voice cards and cleaned them.
  3. when you switched it on, there was no sound.
  4. you smelled smoke.

Did I get that right?

If so, how did you clean the voice boards? What did you clean it with?

3

Sorry to read that Megavoice.

That’s exactly why I always follow the saying: “if it’s not broken, don’t fix it.”
Unplugging, cleaning edge contacts and replugging voice cards, or any cards for that matter, you run the risk of messing something up (especially inside a polymoog) by moving wires around (cracking solder joints) or loosening connectors, or having bad contacts where you had good ones before. Just ask Jareth (Synthpro on YouTube) and he’ll tell you about the potential nightmares of restoring/fixing a Polymoog…




The only real advice I can give you is to follow your nose to the area where the bad odour is most present inside the synth, and go from there. Look for burned resistor, or perhaps busted capacitor, or any visual indication of electrical/chemical damage.

4

thanks guys for responding so quickly…

mr nutty:

I didn t fix anything … the only things that had been changed some years ago was a complete replacement of the led s, succcessfully,

and a totally new spsu from my famous tech heinz weierhorst.

after putting it inside the poly worked fabulously up to now till yesterday up to the cleaning of the cards and reinstallation.

today i opened it up again to examine the connectors, but everything is firm as a rock…

the machine lights up completely, but no sound can be set up by all sliders…

as i said in the introducing, a simultanous chord of all voices can be perceived in the background

ad alain.

i know very well about the nightmares of fixing a polymoog, it s an old bug, and i always was so much in fear to suffer from one

day.

i m so sad about to have lost contact to my former beloryved friend and endless helpful mate heinz who always gave me fixing instructions

and doing all reparations for free

and i and the whole world is mourning of his probably passing away…an extraordinary and so warmhearted character


i ve got one thing to add about the poly.

a technical skilled accquaintance said to me today, if i perceive smoky smell and stinking i should put my fingers on the one and the other

component, exspecially the spsu to feel if there s s.th. hot.

have you boths any idea where i can measure some voltage values…or any other suggestions

every addional help is appreciated extraordinarily

cheers,

christian

5

megavoice, where are you located?

if I were you, I would bring it to a good tech. someone here could probably direct you to one, if we knew your area?

good luck!

6

thank you, so much ummagumma,

i got a hint from atomicsynth:

he gave me the name of synthpro restorations in alabama.

i wrote yesterday immediately, but i havn t got any answer up to now. i hope i ll get some soon —

but i even more hoped to get here some useful instructions how to continue by my own…

i m very far away from you…i m living in germany and as i said, my beloved tech disappeared or died…

so presently i m feeking without pants and i don t know at all what to do…

cheers

christian

7

try this fellow out:

http://www.lintronics.de/index.html

8

Hi Christian-

Since you mentioned wanting to try to fix this yourself…

Do you have the service manual with schematics? If so page 53 or 54 (near the very end of the manual) shows the original power supply schematic. While yours has been replaced by the Heinz power supply the 15 pin connector (P131) is identical. With this schematic I see pin 4 is -15V, pin 7 is +15V and pin 14 is +5V.

I would disconnect/pull this connector from the power supply board and check each one of these voltages with a voltmeter to start. The pins with large gauge green wires are your respective grounds.

I’m not familiar with the Polymoog although I do have a lot of experience with the Memorymoog and Heinz’ power supply. Checking the power rails would be a good place to start.

Also I agree contacting Rudi Linhard might be your best option. This is not a simple board to troubleshoot.

9

I’m not sure about the Heinz PS, but if you disconnect P131 you can’t just probe the voltage rails on pins 4/7/14. On the stock PS each of the voltage rails have Kelvin force/sense lines and the rails on P131 will not appear correct if they are not connected.

The Minimoog PS also uses Kelvin force/sense lines to the VCO card. Many techs neglect them and incorrectly diagnose a malfunction.

Also I agree contacting Rudi Linhard might be your best option. This is not a simple board to troubleshoot.

I did not know that Rudi serviced Polymoogs.

10

Good thought Michael regarding the sense lines but for once my memory is actually good. Just reviewed some old emails from Heinz and his power supply does not require those sense lines to be connected for an accurate reading. However, you do need to short the analog and digital grounds. So for the OP use some clip leads to short together the 3 pins that when connected to the harness have the green wires I mentioned; pins 2, 9, and 12 on the P131 connector.

I’m not sure Rudi services Polymoog, He may however know someone who does in Germany. And he’s always good for a few words of wisdom, and a bad joke or 2 :cry: :wink:

11

thank you guys for your hints, but i ve decided as i m no tech NOT to put my hands on that thing

i ve found a very good tech here in germany and i ve talked to him this afternoon and he immediately said that he s got some polys not long ago for fixing and meanwhile he knows them pretty well…i shouldn t bother about the repairing-costs,
he said when he works he will advance steadily…

the worst thing in the last time was a repairing for 450,00 € but this was an exception…

now i ve to put money aside so that i can pay that man.

he also said that he s got those famous devider chips that are very rare and not to find easily-------

i ve to dig out my old chroma case in the cellar,under all those other carton-packages, that s undestroyable for shipping.

one thing i have to add at the end:

i successfully soldered in the new powerlight on my minimoog and now when i switch it on, he, with only one light is shining like a

christmas-tree and still working and sounding awsome like on the first day of purchase…

thank you all SO MUCH for all your helps and advices and i ll keep you informed in about one year about the poly

and i still love you all more than ever

christian

12

Thats good to hear Christian. I always enjoy looking at service manuals so thanks for the opportunity.
Good luck!

13

If I read correctly, there was advice up above to disconnect the supply connector and check voltages.

I recall that the instructions for Heinz’s supply said not to power it without being connected to load. I could be wrong but that’s what I remember reading back then without now tearing through my studio to find those instructions.

Anyway, I think you are best to not mess with it all yourself and find a good tech. Hopefully the fault is something minor. Best of luck with it.

14

thank you atomicsynth,

as i said, i ve found a tech with great reputation and i already talked to him

i ve to put lots of money aside to pay the expensive shipping and him…

of course i ll let my fingers off as it s too dangerous not being a tech, so thank you nevertheless…

I’ll be back

christian

15

Heinz’s supply is a switching mode power supply and that is correct that they have to have a load connected or the voltage readings will be incorrect.

16

Colleagues,

While you’re at it, could some kind soul do me a humungous favour?

A Polymoog 203a has lost its four, rectangular under-grilles. I’m looking to replace these, but don’t know what they should look like, as there are no photos of the underside of a Polymoog on the net.

Please could someone post a close-up picture of the underside grille of their Polymoog here, so that I can see what an appropriate replacement should look like? Different kinds of grille look different.

With many thanks!

F.