Keywords: Otto Scheller Fig.2.jpg en Fig 2 - Patent of Otto Scheller 1907 Wireless Course Indicator and Telegraph Drahtloser Kursweiser und Telegraph 1907-03-17 Patent No 201496 Deutsches Reich 1907-03-17 Otto Scheller other versions PD-old-70-1923 Uploaded with UploadWizard C Lorenz AG |