GB1363642A - Traffic lights - Google Patents

Abstract

1363642 Radio-controlled road-traffic signals H STEINER Ltd 3 Sept 1971 [5 June 1970] 21630/70 Heading G4Q A radio-controlled traffic light system comprises a first set of lights provided with a radio transmitter, a second set of lights provided with a radio receiver, and switching means operable in response to signals derived from the transmitter and controlled by a timing mechanism to effect illumination of the lights of the respective sets in the desired sequence. Pulses from an astable multivibrator T 1 , T 2 drive a cyclic switch with banks a ... e. Bank a controls the sequence of both sets of traffic lights. Bank c is arranged to energize line I or line II to modulate a radio signal with one or other of two frequencies, which at the receiver is demodulated to operate the red or green light respectively. Bank d utilizes only position 12 which adds the amber light for the red and amber phase. Bank e of the switch connects in sequence to the multivibrator T 1 , T 2 potentiometers gnl, gn2, and rl which can be manually adjusted to vary the time of the green phase of the near and distant lights and both red phases respectively. At the receiver (Fig. 2, not shown) demodulated pulses are used to operate respective solenoids and hence the traffic lights. The circuitry is arranged so that the cyclic switch may be manually operated, the radio signals may be sent by a cable connection, and the signalling sequence may be replaced manually or automatically by a red light or a flashing amber light during a system failure.