years ago i used to sell multisystem tv set (sets that can work in other countries)
England uses PAL I and the signal is UHF
Turkey uses if i remember correctly PAL B which is VHF (big old style "H" shape aerials needed)and PAL G which is UHF (UK style aerial needed)
The sound carrier frequency is different to ours so you may get a picture but no sound if you took a designed only for England TV to Turkey.
Now this is where it gets a bit complicated if you took a English TV to Turkey and connected a Satellite system or DVD of Turkish Video and watched them through the direct connection eg a Scart socket or the yellow and red and white input connectors you would get both picture and sound its only through the Tuner ie the aerial socket that you would have the missing sound problem or if it was a VHF tv channel no picture and sound.
As for power the Turkey system and UK is close enough you just need socket adaptors.
Hope this Helps
Robert
http://www.tenlab.com/tvsystems.html