Korg Poly800/EX800 Users

Somehow, nobody seems to have pointed out the major differences between a
modern-day regulated switching supply and an old fashioned large transformer
type adapter.

The old transformer type adapters are non-regulated, and the voltage varies
with the current that is being used. If it is rated for 9VDC at 300ma, it
probably measures 12-13 volts when nothing is plugged into it. The voltage
will drop as you draw more current, and if your equipment really needs more
than 300ma then the voltage will drop below 9 volts. A large transformer
type adapter that is rated for 1000ma might measure as high as 20V with no
load on it, and only drop to 15 volts with only a 300ma load on it. That
might put a bit too much stress on the 9v to 5v regulator circuit inside the
Poly-800.

 

On the other hand, if you are using a newer switching-type adapter, it is
probably much smaller since it does not need a big transformer in it, and it
will put out a regulated 9V at any current level from 0-1000ma, so there is
no problem using one rated for 1000ma. A/C adapters rarely have markings on
them to show whether they are switching supplies or not. You can usually
tell from the size. If not, just check the voltage output with nothing
plugged into it. If it is 11 volts or higher, it is an old transformer type.
If it is above 15 volts, then you may be shortening the life of some of the
power transistors in the 5V regulator in the Poly-800.

 

Don Backshall

 

  _____  

From: korgpolyex@yahoogroups.com [mailto:korgpolyex@yahoogroups.com] On
Behalf Of Gordon JC Pearce
Sent: Saturday, December 22, 2012 1:40 PM
To: korgpolyex@yahoogroups.com
Subject: Re: [korgpolyex] Re: New Power Adaptor for Poly 800 and question
about multi mods (Hawk)

 

  

On 22/12/12 06:45, Jill Saphic wrote:

> thats what the manual says to use, and the KORG website..
> You will damage your little plastic Poly800 seriously if you go above
> 300MA, maybe not immediately, but it will be all about

You know how your car battery can provide 200A or so to the starter 
motor? How come the little 200mA interior light doesn't blow up when 
you wire it across a 200A battery?

-- 
Gordonjcp MM0YEQ