Toshiba TV - Analogue & Scart Input Black & White

I have just bought a new Toshiba TV with built in digital reciever.
When I switch to the analogue input and search for normal antenna
stations every station it finds appears in black and white on screen. I
have read the manual from back to front but can not find any menu
setting that will fix this problem. It is the same when I connect a VCR
via scart. Again the picture is black and white. Can anyone help?