I've seen this question asked a few times now so thought I would supply as much info on this matter as possible.
Aussie power outlets are the same as the UK. 230-240 volts. Plug sockets are very different however, but you can get around this issue with an adaptor plug.
If you have a High Definition Digital Television, even though Australia and the UK both use the PAL system to broadcast Analogue and Digital TV signals, there is still a good chance your UK bought TV may not work when you get here.
First up...Analogue TV sets
Australia and the UK both broadcast in PAL, but they are differing variations of PAL.
This means the audio has different frequency properties and so, more often than not your UK TV (set up for PAL I) will not be able to receive the audio component of the signal from Australian transmitters (broadcast in PAL G).
Secondly... High Definition Digital TV sets...
Similar issue.
The vision will be received fine by your HD telly, but the sound will more than likely be corrupted by the DIGITAL signal output by Aussie TV stations/broadcasters. The reason is that the UK and Australia ouputs digital audio in different digital based formats. Some in AC3 and some in mpeg which is a similar audio format to DVD audio.
I should stress however that SOME very new Digital TV sets may have an option menu to change this audio system setting for receiving Digital TV signals in other worldwide areas, but unless you can check this out for sure on you particular model of Digital TV, it is best to sell it and start again with buying a NEW one here in Australia.
It is also a good point to remember that the ocean can be rough, and you may need to wrap your precious telly-box in at least a foot of bubble-wrap before placing it into a container for shipping. Screen components on LCD and Plasma TV's are very fragile!
In summary...sell your UK set before moving here and buy a new one in Australia when you arrive.
LCD and Plasma Digital High Def TV's appear to be much cheaper here than in the UK, and if you purchase one here you will have peace of mind that everything will function properly, and that your vision AND audio will be crystal clear.
Mr YG
