Back when Kraftwerk were still doing experimental Krautrock (though they reject that term) and working with Michael Rother and Klaus Dinger. Some might remember this tune as being used as the theme for Newton's Apple.
great clip. i've been looking for that dvd with all the WDR performances on it for awhile. i've seen a bit and remember either tangerine dream or popul vuh playing generator show in a grassy clearing of the woods