Discussion about the Korg PolySix synthesizer

Maybe a bent lead on the ram, shorting itself?

I agree with Andy.  The guy didn't fix it right.

On Thu, Mar 5, 2009 at 7:03 AM, Andrew Jury <andy@networkjabber.com> wrote:
> Hi Milan,
>
>
>
> You should take the board back and tell him he hasn't fixed it properly! ;-)
>
>
>
>
> Seriously, it does sound like there is an excessive load across the
> terminals of the battery. Before you do anything else then please make sure
> that R91 and C40 have been moved from circuit. D15 should not have been
> touched and the new diode (should be a 1N4148 or similar) is soldered in
> place of R40 with the anode facing toward the anode of D15. If the new diode
> is connected in reverse then the 5V rail will be connected to the battery
> whilst the Polysix is switched on! (and also the battery will never power
> pin 18 of the SRAM, if it is not destroyed already!).
>
>
>
> If all the above look right connect an ohm meter across the battery
> terminals making sure the Polysix is disconnected from the mains and the
> cell is also removed. What resistance do you get? If it is below 1K ohm then
> start pulling the SRAM and re-measuring. IC25 and C36 are also candidates
> for failure as they are directly connected to the battery whilst the power
> is off.
>
>
>
> Let us know what you find.
>
>
>
> Cheers,
>
> Andy
>
>
>
> From: PolySix@yahoogroups.com [mailto:PolySix@yahoogroups.com] On Behalf Of
> mekonin
> Sent: 05 March 2009 08:44
> To: PolySix@yahoogroups.com
> Subject: [PolySix] Having problems after battery replacement
> - Show quoted text -
>
>
> Hello good people from polysix support group.
> I have one pretty annoying problem with my beloved polysix and I was hoping
> if you could help me.
>
> I got it back from repair few weeks ago.
> I had the notorious battery problem, and the tech guy fixed almost
> everything except one thing.
>
> He replaced the chip which I think is controling the memory, and it is
> draining too much power.
> We measured almost 30mA, which he says is way too much.
> So instantly, when I put the fresh Lithium battery, the voltage goes from
> 3.3V (or something) to 2.8V, and it takes a few days for the battery to be
> completely depleted (the synth is off all the time).
> He is 99% sure it is that chip that is causing the problem,
> and he suggests me that I find an original one, because he was unable to.
>
> The chip is the replacement for TC-5514, it's 2114 I think.
>
> I have checked if D15 diode is facing the right way, if it's not then the
> battery would be routed to ground with 100 ohm which is something about
> 30mA..
> But it's facing the right way.
>
> I looked at the datasheet for the original TC5514 memory chip and it says it
> needs up to 180mA in operating and 10mA in standby. The 2114 also uses 10mA
> in standby but 100mA in operating mode, so it's a newer and more efficient
> chip. It doesn't make sense that it's this chip that's making the problem.
>
> Thanks in advance guys.
> Cheers,
>
> Milan
>
>
>
>
>
> [Non-text portions of this message have been removed]
> - Show quoted text -
>
>
> ------------------------------------
>
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
>
>
>
>



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-Chromatest J. Pantsmaker
http://www.chromatest.net