Following the overwhelming and somewhat unexpected international success of the album Autobahn, Kraftwerk not only had to complete numerous tours, particularly in the USA, but also had to record a follow-up album in quick succession. Radio-Aktivität was the Düsseldorf-based electronic pioneers’ fifth studio LP following Ralf & Florian and its successful predecessor. And the first on which Karl Bartos (electronic percussion) completed the classic line-up with Ralf Hütter, Florian Schneider and Wolfgang Flür. Furthermore, the sounds were generated exclusively using electronic equipment for the first time, acoustic instruments such as the flute, violin and guitar disappeared completely. The equipment used included a Vako Orchestron keyboard (with choir, string and organ sounds), a Moog Micromoog, a vocoder, as well as the usual synthesizers and Hütter’s Farfisa electronic piano. The electronic percussion instruments, developed largely by Wolfgang Flür, also had a decisive influence on the sound.

Recorded and entirely self-produced in their own Klingklang Studio, the album was released in October 1975 in both German and English versions, once again featuring a design concept by Emil Schult. It was described as a concept album, as it deals thematically with the two areas of radio/ether waves and radioactivity, musically illustrated with cold, at times conventional electropop and emotionless electronic sounds, as well as experimental minimalism and avantgarde elements. On the one hand, the album went completely unnoticed, even in Germany it received very little attention, on the other hand, it was hugely influential, as it marked the birth of synth-pop and new wave, some five years before those genres actually emerged.