Notes. These dates refer to the London-area ITV transmissions - however only 23 of the 24 first-series episodes were screened in the capital. All 24 were broadcast in the Midlands (ATV's own area), beginning on 5 September 1976, seven weeks ahead of London, but ending on 23 April 1977, three weeks after. Forty-five of the 120 episodes were screened by BBC1 from 8 February 1986 to 7
October 1987.
Transmission Details:
Number of episodes: 120 Length: 30 mins
Series One (24) 24 Oct 1976-2 Apr 1977, Sun 5.35pm then Sat 5.15pm
Series Two (30) 30 Sep 1977-23 Apr 1978, Fri 7pm then Sun 7.15pm
Series Three (18) 17 Nov 1978-9 Mar 1979, mostly Fri 7pm
Series Four (24) 24 Oct 1979-4 Apr 1980, Fri mostly 7pm
Series Five (24) 5 Oct 1980-15 Mar 1981, Sun 5.30pm
courtesy of BBCi (bbc.co.uk)