The BBC Testcard F - icon of TV history

Test Card F was a picture created by the BBC in the 1960s to support the development of television technology and help deliver a quality screen image on receiving equipment, and to support the calibration of TV sets by manufacturers, owners and installation engineers.

It was used on television in the UK and about 30 other countries for more than four decades. Like other test cards, it was usually shown while no programmes were being broadcast.

The test card concept dates back to the early days of television, with Test Card A making its debut in the late 1930s. However, it and Test Card B were soon replaced by the more useful Test Card C, which was first broadcast in 1948, with its geometric pattern forming the basis of the more famous subsequent Test Card F.

With its central colour picture, Test Card F was the first image to be transmitted in colour in the UK, and the first to feature a person. It has become an iconic British image regularly subject to affectionate parody and imitation.

The central image on the card shows a young girl, Carole Hersee, playing noughts and crosses on a blackboard with a clown doll, Bubbles, surrounded by various greyscales and colour test signals used to assess the quality of the transmitted picture. It was first broadcast on 2 July 1967 on BBC2. The card was developed by BBC engineer, George Hersee, father of Carole.

It was frequently broadcast during daytime downtime on BBC Television until 1983 and was still seen before the start of programmes until BBC1 began to broadcast 24 hours a day in November 1997, and on BBC2 until 1998, after which it was only seen during engineering work. It was last used in this role in 1999.

Carole subsequently became a theatrical costume designer.