Patent GB-908386-A (GB)
Title: Data read-out system
Filed: 1959-08-28
Abstract: 908,386. Statistical apparatus. STANDARD TELEPHONES & CABLES Ltd. Aug. 28, 1959 [Sept. 3, 1958], No. 29440/59. Addition to 782,408. Class 106 (1). Data represented by marks or holes on a record, Fig. 1, is sensed by a television-type scanner 11, Fig. 2, which repeatedly scans a complete frame of thirty-two rows and three columns A, B, C, a gating means being provided to read out a different column in each scan. In addition to this highspeed read-out, a slow-speed readout arrangement is provided in which data is read out, e.g. to a punching machine, by a horizontal scanning line in each successive frame. In the form described the record consists of photographic film. High-speed read-out.-The scanner makes 525 horizontal scans across the record to cover each frame, this being repeated thirty times a second. In successive frames data from the columns A, B and C in turn is gated out. For each horizontal scan line the generator 12 provides a horizontal synchronizing pulse and at the end of a frame, i.e. after 525 scans, a vertical synchronizing pulse is produced which brings the beam back to the initial position. These vertical sync pulses are counted in a counter 24 which counts to three before resetting. The stages 22, 23 of this counter control gates 18, 19, 20 to trigger one of the phantastron circuits 25, 26, 27 depending on the count. Pulse circuits provide delayed pulses the trailing edge of which occur just before the beam reaches the index marks of the columns A, B, C, respectively. The pulse from the operative phantastron is differentiated at 29 and the trailing edge pulse triggers a monostable multivibrator 31 to produce a gating pulse 32 which, as shown in Fig. 1, coincides with the passage of the beam over the index mark of the appropriate column. Pulse 32 opens gate 16 to allow the signal induced in the photo-cell 15 by the index mark to pass to a delay unit 33 which consists of four delay devices in parallel, the resulting four pulses being coincident with the passage of the beam over the four data marks of the row being scanned. In unit 34 these four timing pulses are used to gate out the signals derived from the marks in the corresponding column, marks in the other columns being ignored. After the completion of a frame of scans, the counter 24 increases by one and the next column is read-out. Slow-speed read-out.-Horizontal sync pulses, one for each horizontal scan line, pass from generator 12 to a counter 36 which has a count of 526, that is one more than the number of lines in a frame. The output pulses from counter 36 therefore occur, in successive frames, in coincidence with successively lower lines in the frame. A multivibrator 37, set by this slowspeed read-out pulse, passes a signal via inverter 39 to prime gates 40, 41, 42. Signals are applied to each of these in turn by a step-switch 43 stepped after each 525 frames, that is when a vertical sync pulse coincides with the output from counter 36. Gates 40, 41, 42 apply signals to the phantastrons 25, 26, 27 respectively to read out the corresponding column as described above. To allow a different column to be read out at slow-speed from that read out at highspeed, an inhibiting gate 17 is closed by the output of multivibrator 37 to suppress the horizontal sync pulse applied to gates 18, 19 and 20. Control of the phantastrons is accordingly from gates 40, 41 and 42 for the one horizontal scanning line. Specification 894,564 also is referred to.