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Subject: Re: [PolySix] MG section problem

From: Jed Jorgensen <jed.jorgensen@gmail.com>
Date: 2010-05-14

Hi Vincent,

Did you fix the two PCB errors noted here (#1 & #3):
https://sites.google.com/site/jedjorgensen/klm367a/images/pcb-bugs-errors

<https://sites.google.com/site/jedjorgensen/klm367a/images/pcb-bugs-errors>Also,
did you calibrate the board following the build as per the service manual?

Jed

On Thu, May 13, 2010 at 3:07 PM, kluberrrrr <KLBR@free.fr> wrote:

>
>
> Hi everybody,
>
> I'm quite desperate here, so I hope someone could help me a bit especially
> because I'm not very good in English and I'm not an electronic guy!
> A couple of years ago I found a polysix which had the famous leak battery
> problem, so impossible to play on it.
>
> I tried to repair the KLM 367 but with no success.
> Then i discovered the Jed's project
>
> Today I've just finished to solder all the parts on the KLM-367A clone
> board.
> I put the board back on my P6. Then I turned it on.
>
> First, the programmer panel seems to work fine, Led button repond when I
> push them
>
> BUT there is no sound at all. Just some attack sound, some 'blops'.
>
> When I hold a key down, I can hear the note coming very slowly and fade
> out. Just like the LEd of the MG panel fading In and Out very slowly.
>
> The Mg frequency, delay and level's knobs don't affect the modulation. Even
> if the modulation level is at 0, the sound is fully modulated
>
> So I guess it's the MG section which seems to not work properly. It looks
> like it is stuck on a very slow frequency and there is no way to cut the
> modulation.
>
>
> Also cutoff, resonance, eg int, keyboard track knobs don't seem to change
> the sound.
>
> When I built the new Jed's PCB, I used from the old board the mask rom IC,
> the TC5514APL-3 IC, the two LM13600 ICs and the 2SA798
>
> What do you think? Is it possible that one of the Ic is dead? Or does it
> look like the problem is deeper?
>
> Please excuse my poor english !
>
> Cheers!
>
> Vincent
>
>
>


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