CANNING THE RADIO PROGRAMME

Hawke's Bay Herald-Tribune, Volume 81, Issue 31, 30 October 1937, Page 15

CANNING THE RADIO PROGRAMME

% A Permanent Record

pBESENT since .the inception of the radio era has been the problem of retaining & permanent record of the many magnificent programmea offered by invention, The principle of the phonograpMc dise has been applied with, little suecess, owing to its coatly maintenance, and the inability of the dise' to hold a musical eonjfcinnity of more than three or four minutes* duration. Thus the Teflphon, a new invention without either of the abovt drawbacks, was the source of great general interest when ahowa *t the Leiprig Fair recently. - This inatrument records a continuous programnie of any given length without any supervision, once it has been aet in iQotion. The notes of music, or aound® of speech, are registered on e *»m, which can immPdiately be used to render a xepetition of the presentatioa just xecorded, A film some one hundred xaeters in length will "play" eontinuously for about twenty-four hoars. The apparatus is wholly automatic, and chronicles the programme with ' minute exaetness. Cohtraiy to the praotice of the talking motionpicture, the sonnds ftre not photographed on the film but are engraved thereon by"a sapphire stylus, The whole apparatus is attached lik© a loudspeaker to the back of the radio, and the broadcest enters a sort of cutingbox, wherein the music is cut in grooves into the film. A special film which takee impresslons on both sidos acts as a sound-track,. while the actual film itself is one continuous roll, beginning and end joined together. One hundred grooves can be cut into each roll, at.a

distance of 0.25 millimeters apart. The film rotates at a speed of 22.5 centimeters per second in the recording of speech, and 45 centimeters per second in the registering of music. A pointer on a. scale indicates just how much of the film has been used, and-on this scale also can be set dowa the names of the various itepis recorded. Each time the film is run off, this scale can be xe-attached, thus co»stituting an index to the contents of the roll, and making possible an accurately catalogued library of prqgramnaes. The turn of a knob sets the devine going, and in the "play ing" of the film, a sapphire stylus must be used, as in the original registering. One stylus has a lifetime of approximately eight hundred hours. . Of special interest is the automatie contrivance which removes, by a simple process of suction, the particles of film loosened in the original cntting of the sonnd-grooves in the roll. The uses of the ' ' Tefiphon ' * are manifoid: Telephone conversations, conferences, court-xoom proceedin'gs, dictation, can all be quite easily "written" into the film, which also possesses the unique advantage, by means of a switch, of enabling a full halt in the recording to take place, and a complete review of what has gone before to be made, withopt the neceasity of yolling the film raqfcwards. A roll of film will givq oue hundred t'performances" withont any noticeable degeneration in the quality of the soundj. which is quite adequate for most purposes.