GB1465411A - Arrangement for representing a plurality of analogue electrical input signals occuring on separate lines - Google Patents

Abstract

1465411 Cathode-ray tube displays HARTMANN & BRAUN AG 22 Aug 1974 [24 Aug 1973] 36976/74 Heading H4T The magnitudes of a plurality of input analoque signals are displayed on a conventional cathode-ray tube video display either as a generally horizontal trace (BG 1 ) or as a series of vertical lines (BG 2 ). Each analogue signal ME 1 , ME 2 ... ME n is fed to one input of a respective comparator VM 1 , VM 2 ... VM n the other inputs of which receive an analogue input AW indicative of the vertical position of successive lines of a normal raster scan. The quantity AW is produced by a digital-to-analogue converter DA supplied with the binary addresses BA of successive lines comprising the output of a counter ZZ which counts line pulses Z1 derived from a video signal generator VSG which also supplies a reset pulse RS of picture frequency to the counter. When amplitude equality occurs between the analogue inputs ME and the analogue input AW the comparators produce outputs which are fed to a digital multiplexer MP. The latter is controlled so as to supply the outputs VEM of all of the comparators in sequence to a comparator logic circuit VL by means of a second line pulse counter MZ which is controlled by the output FT of a pulse generator TG of adjustable frequency and pulse width synchronized by the line pulses Z1 the adjustable frequency allowing the number of the signal elements in the output of each comparator, which are to appear in each line of the display, to be adjusted and the adjustable width at input FR to the logic circuit VL allowing the width, i.e. the duration, of each signal element to be adjusted. The above manner of operation results in the production of a display of the BG 1 type. When a display of the BG 2 type is required comparator VB compares the reference point of the displayed voltages, a voltage corresponding to the lowest line of the display, i.e. the zero reference, with the analogue value AW indicative of line position, the comparator producing an output which causes the tube beam intensity to be increased as it progresses upwardly from the lowest line (the zero reference) until the occurrence of an output from multiplexer MP corresponding to the measured value. The trace is then blanked and the height of the resulting vertical line is indicative of the measured value.