Korg Poly800/EX800 Users

The wall wart should be providing a consistent 9V DC output.

If you're seeing 13 volts at the input of the Poly 800 then you need to get a 9V DC wall wart. 13 volts will overload the on board power supply control circuits.

Mike

--- In korgpolyex@yahoogroups.com, "n8" <natere2ster@...> wrote:
>
> hi list.
> 
> just joined and have a question perhaps someone can chime in on...
> 
> i have a korg poly 800 mkI here on the bench with a power issue.
> 
> when on batteries it runs fine, but will not run off the wall wart...
> 
> the wall wart works ok, i tested the voltage on the dc plug and it is spitting out 13V const.  I read that at the DC jack as well...
> 
> The problem so far looks like i do not get the +5V on the connector CN06A on pin 10....is that correct?
> 
> I get the pull DC in on pin 11 so that is good!
> 
> But i need to get that 5V on pin 10 so it can be sent to the chorus board, then to the volume / switch on?
> 
> from the rough schematics i see that Q1's base and collector are tied to this rail, and its emitter is tied to the DJ jack....
> 
> Q3 is E-C is on the 5V line, and its base is tied to Q2 tranny which is tied to Q15 which is tied to gnd.
> 
> Is this correct?
> 
> I assume its one of the power switching transistors are bad, how can I confirm this?  I de-soldered Q1 and have it on the breadboard.
> 
> I used the standard transistor PNP tester circuit, as seen here:
> 
> http://www.kpsec.freeuk.com/trancirc.htm
> 
> It seems to work fine, I can turn the led on when the switch is closed and turn it off when its open...
> 
> So i guess its ok and i should put back LOL?
> 
> Anyone know of any other transistors to check?
> 
> I am looking at Q3 for some reason....
> 
> What steps down to voltage from the DC jack in out to the +5V?
> 
> I assume once i get the +5V i will be ok...
> 
> i just keep looking at Q1 and Q3 cause they are both tied into GND, the DC jack in, and the +5V rail.....
> 
> Sorry for all the questions i am noob!
> 
> Cheers,
> 
> Nate
>