Abstract: A system for controlling the alert and response indictors of an emergency vehicle permits the operation of one alert device, such as a police vehicle lightbar, to automatically initiate the operation of a video camera, thus providing a record of an emergency event without requiring the operator of the vehicle to specifically turn on the camera. The system also provides isolating diagnostic functionality that simplifies system troubleshooting.

Abstract: A portable, self-contained, programmable electronic voting machine includes a motor-driven scroll mechanism carrying a plurality of printed ballot sheets, the scroll mechanism presenting to a voter, in a controlled manner, only a preselected portion of the ballot sheets at any one time. Each selected portion of the ballot sheets is viewed by a voter through a window panel along opposite vertical edges of which extend single columns of push-button switches positioned next to voter selections on the portion of the ballot sheets then being viewed. A voter depresses appropriate push-button switches to make vote selections. The voting selection process is repeated as the voter, by actuating the scroll mechanism, selects other portions of the ballot sheets. A voter then casts his vote using a separate vote casting switch.

Abstract: The invention is an electronic siren comprising in combination circuitry for generating one of a square wave siren and intelligible audio signal and a power output amplifier for audibly reproducing the signal. The amplifier includes transistor circuitry having base, emitter and collector means and a first circuit for coupling the signal-generating circuitry to the base means and one of said emitter and collector means for driving the transistors of the transistor circuitry into saturation in response to the siren signal. The first circuit includes circuitry for applying a dynamic biasing voltage derived from the siren signal to one of the emitter and collector means in phase with the voltage of the siren signal applied to the base means and of a plurality and opposition to the potential drop of the junction of the base means and the other of the emitter and collector means.

Abstract: The invention is an electronic siren comprising in combination means for generating periodically occurring charging pulses at a selected one of a plurality of predetermined repetition rates, time-constant determining means coupled to the pulse generating means for generating a repeating voltage wave form in response to the charging pulses and means coupled to the time-constant determining means for generating a square wave signal having a frequency proportional to the instantaneous voltage of the voltage wave form. Coupled to the square wave generator is an output circuit which includes a first pair of transistors and first circuit means coupling the transistors to the square wave generator for driving the first pair of transistors individually and alternately into saturation in response to the aforementioned square wave signal.