Voice-activated radio-dispatched alarm
A voice-activated radio-dispatched alarm, or VARDA-alarm, is a type of burglar alarm that, when activated or "tripped", broadcasts the type of the alarm and the transmitter location over the local police radio frequency using a pre-recorded audio message. In 1968, the voice-activated radio dispatched alarm (VARDA), was invented.
Source: Wikipedia — Voice-activated radio-dispatched alarm (CC BY-SA 4.0)