My TV has a button with an icon of a circle with an arrow going into it - if I press this button a window appears with the various signal input choices (your TV does not know that you wish to watch Digital TV) so you have to tell it.
Your external box probably tunes and decodes Digital signals and will connect to the TV via a SCART lead on input AV1 or perhaps AV2 - so if you select one of these on the screen using the up and down buttons the TV will display that input. If you have a conventiuonal Coaxial aerial cable connection into the TV you can use the same method to select DTV (digital TV) as the internal tuner to use.
Quite why the TV changed to showing Analogue signals I can't say.
If you're unable to get the signal you want you may have a connection problem with a scart lead or coax cable - it takes only moments to check them.
The remote control will very probably not be of any use in solving your problem - just the buttons on the TV and the cables that connect to it.
Peccavi
January 2010
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