Johnnie Walker celebrates the 70s by playing classic tracks, archive sessions, and he talks to the electronic musician Gary Numan about his early days in Tubeway Army, how his obsession with synthesisers began and his 70s hit Cars. American rock musician and singer-songwriter, Bob Seger is this week's music focus and in Radio Rewind there is some 70s radio archive of Emerson, Lake and Palmer's Carl Palmer.