Oberlin Smith's ideas in magnetic recording were used by Valdemar Poulsen when he developed magnetic recording successfully.
However, Danish physicists Valdemar Poulsen and P. O. Pederson were able to increase the frequency of Duddell's oscillator to the radio range, and in 1902 patented the Poulsen arc radio transmitter, the first transmitter which could generate continuous waves.
Valdemar I | Valdemar Poulsen | Valdemar IV of Denmark | Valdemar I of Denmark | Valdemar's | Valdemar of Denmark | Jógvan Poulsen | Etiyé Dimma Poulsen |
Magnetic tape was invented for recording sound by Fritz Pfleumer in 1928 in Germany, based on the invention of magnetic wire recording by Valdemar Poulsen in 1898.