A modern version of the television testcard - featuring Myleene Klass - will feature on Sky's HDTV service.

The original, featuring a young girl playing noughts and crosses, was displayed on terrestrial channels while nothing was broadcast, and helped engineers with tuning.

Now Sky has breathed new life into the old scene in a card to show while its high density channel is off-air.

Rather than eight-year-old Carole Hersee, the daughter of a BBC engineer, it will feature Klass, formerly of Hear'Say and I'm A Celebrity...Get Me Out of Here!

And, instead of sitting patiently, she will climb out of her seat and explain to viewers the benefits of HD.

Klass commented: "I'm really excited to be the face of the Sky HD testcard and to be taking part in a little piece of TV history.

"For me, the card evokes nostalgic childhood memories of staring at the TV waiting for Playschool."

Chris Johns, chief engineer at Sky, added: "Myleene looked great in the jungle and looks even better in HD."

HD-enabled viewers can see the Klass card on Sky channel 268.