Oh...a lot that have already been mentioned and probably loads I can't think of. It's not so much that I want them to come back, rather that they were important to me at the time and remind me of my 'yoof'. Some have been repeated and it's the ones that are never repeated that you miss the most. Thank God for youtube.
Blake's 7
The old tv series of the Hitchhiker's Guide To The Galaxy.
Quatermass
Poldark
The Secret Life of Us - Australian?
The Likely Lads
Upstairs Downstairs
The Tomorrow People
Reginald Perrin
Rising Damp
Cagney & Lacy
Starsky and Hutch
Bouquet of Barbed Wire (It was a hot summer and made an impression on my young mind!)
Citizen Smith
The High Life (Dearie dearie me - very like last year's UK Eurovision entry!)
Flambards - the music was very distinctive.
Vaguely remember The Cedar Tree - eons ago, along with Crown Court!
I remember Eerie Indiana.
Lots of American series, many already listed.