Patent GB-1104267-A (GB)
Title: Improvements in or relating to electrical illuminated message display signs
IPC: G09G3/24
Filed: 1966-04-18
Abstract: 1,104,267. Illuminated display sign. GENERAL ELECTRIC CO. 18 April, 1966 [19 April, 1965], No. 16858/66. Heading G5C. An electrical illuminated message display sign has a plurality of serially connected display lamp panel sections controlled by a plurality of serially connected logic transfer circuits for controlling the illumination of the lamps in a desired sequence, and, disposed within the logic transfer circuits, electric circuit means for causing predetermined optical effects, for example (a) switching means for reversing the direction of character motion; (b) a time delay circuit which determines the time between the initiation of extinguishment of lamps in one column and the illumination of lamps in the next successive column; (c) means for causing a moving display of characters to become sequentially stationary in a selected number of successively connected panel sections with elimination of selected characters on the portion of the sign defined by the selected number of panel sections, while any other displayed characters continue moving; (d) means for controlling the illumination of the lamps in a row by row sequence; (e) means for transferring the logic determining the next corrective state of the lamps while the lamps are in their present illumination state. Fig. 8 shows pulse generator and voltage switch circuit 32 and logic transfer circuits 37 including solid state devices 67, 68, 69 associated with lamps 64, 65, 66. (a) With switch 108 in the F position, the incoming clock pulse Vc resulting in the momentary conduction of transistor 56 give rise to voltage pulse VpcF on common bus 79 and the transfer of logic in the forward direction, for example the transfer of a non-illuminated state of lamp 65 to lamp 66. In the reverse (R) position of the switch, voltage pulse VpcR is generated on common bus 107 and logic is transferred in the reverse direction. (b) Time delay circuit 110 provides a delay between the time at which transistor 56 is momentarily rendered conductive and the time of generation of voltage pulse Vpc. (c) Auxiliary circuits (32a, 37a) (Fig. 9a, not shown) are used in conjunction with those of Fig. 8 to " freeze " part of the message by inhibiting the clock pulses Vc supplied to circuit 32, to prevent logic transfer. When switch (119) is operated into the freeze (F) position, the next clock pulse divided in frequency by circuit ( 113) causes non- conduction of solid-state device (67) and forward bias of diode (114) giving a D.C. voltage at the Vc terminal 61 of module (8) and preventing transfer of any further logic through this module. (d) If the message is to be written row-by-row, a separator pulse generator and voltage switch circuit is provided for each row of logic transfer circuits (Fig. 10, not shown). (e) In Fig. 11 (not shown), the logic and lamp power conveying circuits are separate. Lamp intensity control voltage (Vp) is fed to the gate electrodes of solid-state devices (151), (152) and the cathodes of devices (151), (152) are connected to the display lamp (66). The output (Vlo) of the logic circuit is connected to the gate electrode of solid-state device (69) (c.f. Fig. 8). With switch (154) in the W (" write while hold ") position, lamp (66) can be caused to light by a pulse (Vto) and will then remain lit as D.C. source (155) supplies holding current to device (69).