GB1201122A - Improvements in or relating to waveform storage and reproduction systems - Google Patents

Abstract

1,201,122. Recording and play back; data storage. INTERNATIONAL COMPUTERS Ltd. 17 Feb., 1969[5 March, 1968], No. 10674/68. Headings G4C and G5R. In a computer installation spoken matter is reproduced by selecting and reproducing recorded words at a high rate from a first store, writing the words into a buffer store from which they are read at a lower rate for audible reproduction. The first store comprises drum 10 having an outer surface 11 of magnetic recording material which carries a plurality of pre-recorded tracks 12 each comprising a digital address portion 12A and a speech word portion 12B. The drum and the multiple head assembly 13 are rotated such that the tracks 12 are scanned in succession at a very high rate and the head circuits, which are capable of reproducing signals having frequencies up to 12 Mc/s, apyly the signals to a comparator 18. When a read address corresponds to that applied from register 16, gate 20 is enabled and the associated word is written into buffer store 21 which includes a two gun cathode ray storage tube 22. The writing is controlled by signal generator 23 which is triggered by the comparator signal and supplies the time base signal to write the word into line 22A. A read deflection signal is generated in unit 24, the time base rate being determined such that the line 22A is read out at a rate which produces an audible reproduction of the word from speaker 26. When the word is completely read out null detector 30 operates to restore unit 24 and to signal that the address of the next word may be inserted in register 16. The buffer store may use two lines 22A, 22B one of which may store a word being read out whilst the other is ready to receive, or stores, the next word. Switching is carried out by flip flop 32.