Dharam;

I looked up the Acer Extensa 390 on acer's website
http://www.acersupport.com/notebook/html/ext390.html
In section 4.5.2 of the .PDF manual it indicates that for
international travel you only need the correct
power cord. In the specification chart it lists the ac adapter
as:"100-240V AC AutoSensing Adapter"

Because a transformer uses induction from the primary coil
to the secondary windings, it is possible  to make dual voltage
adapters.
I have several laptops here - compaq, ibm, toshiba, and a micron, all
the ac adapters
for them say "input voltage 100-240v"
If in doubt check it before you leave by plugging it  into a 240
outlet with the
proper adapter/powercord  and use a voltmeter to see if it produces
the proper voltage.

     |
  --|---------------------------
     | ><>  Larry  Fisk   <><
     |      Fisk Computers
     |      Fruitvale, Idaho

>Dharam wrote:
> Normally, I would not hesitate. In this case, however, there is no
visible
> switch on the adapter(transformer) and it makes me wonder how the
vendor can
> build one that will supposedly 'automatically switch voltage (110 to
240) and
> frequency (50-60). From the feedback so far, I am becoming
exceedingly
> hesitant to try, in case i lose the laptop.

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