Sort of. Today’s HDTVs are much more global than televisions of previous generations. Still, while you may be able to plug it in and turn it on, there’s a possibility that there won’t be any content.
Before the digital transition in the US, it was almost impossible to use an American television in most of the world. It wasn’t just the shape of the plug, it was that most countries outside of North America used a completely different broadcasting system. Sadly, that part is still true. While standard definition TVs used the NTSC, PAL or SECAM systems, today’s HDTVs use ATSC or DVB for their tuning. DVB is a set of open standards that work within many countries for digital TV transmission either from land-based towers or from satellites. The US uses ATSC, which was developed to strict American guidelines and contains Dolby Digital sound, which is patented. In fact, much of the broadcast technology is patented and therefore unavailable to some parts of the world but specifically Dolby Digital is rarely used outside the US due to strict licensing requirements.
Still, this isn’t 1975, right? There’s more to TV than just broadcast. So, let’s say you took your television overseas. You looked in the owners’ manual and found that you were able to set it to use the 50Hz electricity used in many nations, and set it (as necessary) to use 240 volts rather than the customary 120 of the good old U S of A. Let’s say you were incredibly fortunate that you even had an appropriate power cord.
When you powered on your TV, you might find that you could connect a DVD or Blu-ray Disc player to it and that you even got both sound and picture. Then, you’d try putting in your disc and … nothing. Both DVDs and Blu-ray Discs are “region coded.” Discs designed for North America simply won’t play in overseas equipment unless it is specially designed. There, just as here, most players aren’t specially designed to do that.
That said, you could connect the TV to an external tuner if there was one available, possibly to a satellite or cable box, and it would work just fine in many cases. Really though, it’s a bit of a gamble and the better thing to do is leave your TV in your living room and use something that’s available at your overseas destination.