Circuits for the Remote Selective Display and “Clearing” of Memory “Tracks”

The system for remote display and “clearing,” i.e., the removal of stored data from each track, is based on diode selection matrices. The instrument panel for the user group has an additional five coaxial telephone lines for this purpose (in a common cable with the other groups). Two lines (four wires) permit selection of sixteen tracks in binary code. For this the potential of the cable wires (0 or −20 V) is inverted again at the input to the selection matrix, and then in an ordinary diode network linear sampling of one input of the track logic block is made. The matrix output which does not carry a negative potential is chosen, as only it controls the given diode-resistance network for transmission of the code signals from the given logic block (Fig. 1). The common output of the transmission network triggers a blocking oscillator, and from the output winding of the latter an illumination signal is transmitted via a third coaxial line to the display network, which is situated in the user group instrument panel.