This playlist (which you can also find on my Youtube Channel) includes all of Sparks British chart hits in chronological order;
1974 This Town Ain't Big Enough For The Both Of Us #2
1974 Amateur Hour #7
1974 Never Turn Your Back On Mother Earth #13
1975 Something For The Girl With Everything #17
1975 Get In The Swing #27
1975 Looks, Looks, Looks #26
1979 The Number One Song In Heaven #14
1979 Beat The Clock #10
Unfortunately, I couldn't find a decent moving video for Amateur Hour, but this does have decent sound quality. You'll also have to put up with DJ Steve Wright desperately trying to be amusing about keyboardist Ron Mael in The Number One Song In Heaven.
Sparks last chart hit in the UK was a re-release of This Town Ain't Big Enough For Both Of Us, which reached #40 in 1997. The song was originally a No.2 hit in 1974, which was the group's biggest hit.
During the 70s, Sparks were actually a band (rather than a duo) and had a very different, rockier sound. The synthpop sound wasn't used until they teamed-up with the Italian music producer, Giorgio Moroder, for the album No.1 in Heaven, which was released in 1979. Moroder also produced the next album Terminal Jive.
The band have used a blend of both real instruments and synths since then, at times venturing more towards pure electronica and dance music. American Brothers Russell and Ron Rael decided to use a lighter synthpop sound for their 1983 album In Outer Space. Their 2009 album, The Seduction Of Ingmar Bergman, was actually a pop musical, rather than a collection of individual tracks.