Abstract: A radio transmitter activated traffic signal control including a radio transmitter carried in the emergency vehicle and activated to transmit a signal to the traffic signal lights at each intersection approached by the emergency vehicle which in turn activates a relay within the traffic light controls which relay disconnects the normal sequencing controls to the traffic lights and activates a timer delay relay which initially energizes the red light in each traffic signal via a blinker to cause a flashing red signal to be activated at all lights and subsequently, after an adjustable time delay period ranging from 5 to 8 seconds, energizing each red light in a steady mode. After the transmitter signal is sufficiently attenuated by the emergency vehicle proceeding a sufficient distance beyond the intersection, the receiver-activated relay is again de-energized, causing the normal sequencing and timing controls of the traffic signal to again be connected to the traffic lights for normal operation.