BBC1 Schools Broadcasts - The Dots 1978-1981

From sometime between 78 and 81, this is what they used to do between programmes for schools and colleges on BBC1. They would announce the programme, but instead of it starting straight away, they would have an interlude, with a countdown clock filling the last 60 seconds. These large gaps helped get people in and out of the TV room when VCRs were not so common.
Many people like me remember sitting there with hands poised as pretend guns, shooting these 'dots' off the screen, and being told off for it ;)