 The following year a fellow German, Louis Blattner, working in Britain, licensed Stille's device and started work on a machine which would instead record on a magnetic steel tape, which he called the Blattnerphone.The tape was 6 mm wide and 0.08 mm thick, travelling at 5 feet per second; the recording time was 20 minutes.The BBC installed a Blattnerphone at Avenue House in September 1930 for tests, and used it to record King George V's speech at the opening of the India Round Table Conference on 12 November 1930.