This article is from the Hungarian FAQ, by Zoli Fekete fekete@bc.edu with numerous contributions by others.
The electricity is 220 V, 50 Hz. The frequency, in fact, fluctuates a
lot, but it doesn't cause any problem when operating computer devices.
(Don't trust too much your plug-in clock radios though.) If you are
from any country running on 110 V or around, due to complications in
voltage conversion, a battery driven laptop or notebook is your best
bet. However, if you decide to take your desktop system, printer, etc.,
you have a good chance that the device can also be operated on 220 V.
Check it first before you go through unnecessary trouble. If not, you
have to apply 220 V to 110 V AC converters (you might need more than
one; check the power ratings of your devices & converters). WARNING!
Your converters should be designed for *electronic/motorized devices*.
Refuse any converter for *heating appliances* even if its power rating
is much higher! These converters are not real transformers, and can
cause major damages to your electronic devices.
Also make sure you are able to connect to the Hungarian grounded power
outlet, because that's what's recommended for your appliances.
Therefore you should try to find grounded plug adapters and/or voltage
converters. Connecting to ungrounded outlets causes possibly no harm,
but for your own & your devices' safety grounded connections should be
preferred.
 
Continue to: