As you may know, there are transformers and converters to get to 110v.

It has been explained to me that electricity flows like a sine wave - a transformer transforms the wave to the correct (lower) amplitude while the converter lops off the tops of the waves to limit the amplitude.

Therefore, basic electronics, such as a heating element, are ok with the more rudimentary converter method of stepping down the voltage while more complex electronics, say a wifi router, requires the more refined transformer method.

Of course, I'm not an electrician so I could have mistakenly swapped the terminology, and don't turn the above into a crib sheet for a physics exam.

What you will need will depend on how complex your expresso machine is. A FrancisFrancis is less complex in many regards than a electronic Krups.

Anyhow, the converter is cheaper than the transformer.. and either is pretty darn expensive in a place like Big C - they were like $30+ so I didn't buy.

I ended up getting one through the video game stores - they sell them there because most of the game systems are Japanese imports running on 100v. The video game guy got it for me for 100k VND or so.

There are video game shops in and around Finnegan's Pub, and along Ha Ba Trung as you head towards the Vincom shopping center.