Who patented the Magnetic Recorder? How it was modified as a tape-recorder for domestic use?
The first MAGNETIC RECORDER.
The first MAGNETIC RECORDER was the Telegraphone, patented by Valdemar Poulsen, a Danish engineer employed by the Copenhagen Telephone Co., in 1898. It was demonstrated publicly for the first time at the Paris Exposition of 1900. The Telegraphone used magnetized piano-wire running between spools at 7 ft a second, and recordings could be erased at will. Commercial production was undertaken by the American Telegraphone Co. of Springfield, Mass. in 1903, the machine being promoted as an office dictation apparatus and also as an automatic telephone-message recorder. An improved model with DC bias was employed by Prof. Lee De Forrest in 1913 for talking-film experiments he made at the Biograph Studios in New York. The Telegraphone suffered from a number of drawbacks that made its appearance as a commercial product somewhat premature, chiefly poor amplification—reception was via earphones–and its failure, tough had to do more with inept company management than anything radically wrong with Poulson’s recording system, which was not only sound in principle, but provided the basis on which later inventors is the field developed commercially successful apparatus.
The first TAPE RECORDER (i.e. a magnetic recorder using tape instead of wire) was the Blattnerphone, originally employed in 1929 for adding synchronized sound to the films made at the Blattner Colour and Sound Studios, Elstree. Designed by film producer Louis Blattner, it was based on the patents of German sound engineer Dr Kurt Stille and was also the first successful magnetic recorder with electronic amplifications. The first commercially produced Blattnerphone was acquired by the BBC in 1931.
The first radio programme made up entirely of taped items was Pieces of Tape, recorded in 1932. King George V’s Christmas speech was recorded on the Blattnerphone the same year, arid early in 1933 the BBC set up a special Recorded Programmes Section. The Blattnerphone used steel tape on large reels and was extremely bulky, so that it was generally necessary to carry the voice to the machine (via wire relay) rather than the machine to the voice.
The first TAPE RECORDER USING PLASTIC TAPE was the Magnetophon, produced by AEG of Berlin in 1935. The tape speed was 30 in a second, and though the earlier models had a performance inferior to the Blattnerphone, the running cost of only is a minute compared favourably with the latter’s 7 s 6 d a minute.
The first TAPE RECORDER PRODUCED FOR HOME USE was the Soundmirror, marketed by the Brush Development Co. of Cleveland, Ohio in 1947. The tapes used with this machine had 30 min playing time and cost $ 2.50.
