the 9V dc line is designed to disconnect the battery power when the ac adapter is plugged in, (not powered, just plugged in)
this is a mechanical make/break as part of the socket design, and is working as expected.
note that the Ac adapter needs to be tip negative, not tip positive as most ac adapters are.
its very easy to check with a multitester which way around the power supply is configured, and most even have it printed on the ac adapter.
the ac adapters i use are generic brand 9V 450ma ones, and i have reversed the polarity by cutting and re-soldering the lead to the plug.
that your unit works on batteries tells me that the adapter is most likely the cause.
there is some reverse voltage protection in the korg, via a zener diode, which will short the incorrect polarity out of the unit, but i wouldnt suggest leavin it plugged in like that,
and better to make sure the adapter is actually tip negative 9V before plugging it in
best regards,
Marcus Wilson
On 28/09/2007, at 5:14 AM, funkymonkeypeter wrote:
I just got a Sega 9v PS as sugested in a previous post. When i plug
it in though the unit will not turn on. Even when there is no A/C
going to the P/S the POLY will not turn on even with batteries 6
C-cells installed. As soon as i unplug the 9volt DC line it will
power up. I get the impression that this might also be related to the
fact that the headphone out does not work as well (line outs work
fine). Is this an easy fix or should I just put in a DTDP switch to
go from batteries to DC in?
Thanks.