Abstract: Techniques for communicating lighting commands through a controller area network (CAN) bus of a light bar system include generating a light code message. The light code message has a metadata portion and a value portion. The metadata portion defines a purpose of value portion. The value portion controls a state of a lighting device (e.g., a keypad's LED brightness or activation of a directional light module) in the light bar system. A data field is generated by encapsulating the light code message with an ISO-TP single frame header and a message subtype. A CAN controller generates a CAN message having an extended frame format and the data field. The CAN message is then transmitted through the CAN bus.

Abstract: A multi-frequency alarm (10) generates a narrow band noise (MFA-87, -97, 102, -107) warning of a presence of a vehicle. The alarm includes noise signal circuitry (30) generating a pseudorandom bit stream to produce a noise signal that exhibits a multi-frequency spectrum; an active low-pass filter (40) receiving the noise signal and producing a narrow band noise signal, the active low-pass filter configured to establish for the narrow band noise signal spectral characteristics exhibiting a high-frequency noise signal magnitude roll-off that attenuates frequencies greater than 4 kHz; an audio amplifier (50) producing an amplified narrow band noise signal; and an audio speaker (60) responsive to the amplified narrow band noise signal and configured to emit narrow band noise sound derived from the narrow band noise signal.

Abstract: A rotating beacon including a plurality of light emitting diodes and a plurality of reflectors is disclosed. The light emitting diodes are attached to one or more printed circuit boards mounted on a base. The reflectors gather light from the light emitting diodes into a plurality of beams which are directed away from the base. A motor and shaft assembly rotates a mirror element. The mirror element is arranged to reflect the beams into a horizontal plane of the rotating beacon.

Abstract: A rotating beacon system and a method for synchronizing multiple rotating beacons. The rotating beacon system includes two or more rotating beacons and a feedback based control system adapted to sense an angular position of each of the two or more rotating beacons and generate two or more digitally controlled currents, each of the two or more digitally controlled currents conducted to an associated rotating beacon, the two or more digitally controlled currents driving and controlling the angular speed of each of the two or more rotating beacons to regulate a pre-selected phase relationship between multiple beacons.

Abstract: An audible alert device includes a pulse width modulated signal generator. The audible alert device and method for manufacturing the audible alert device also provides resonant frequency and decibel peaking capabilities. Resonant frequency and decibel peaking routines may conducted at the time of manufacture, upon startup of the alarm or during operation of the alarm. The audible alert device may be programmed during a manufacturing step to exhibit a selected operation mode so that one circuit may be manufactured and programmed to operate in any of a number of operation modes or device configurations. A programming station allows an audible alert device to be programmed during a manufacturing step to exhibit a selected operation mode. Programming may occur by connection of the audible alert device to the programming device by one or more audible alert device power conductors.

Abstract: A warning device including a status and function indicator circuit for indicating the status and function of the warning device. In a visual warning device such as a strobe light, the status and function indicator circuit includes a status output device such as an LED. The LED and associated circuitry are configured to indicate both proper operation of the visual warning device and, in the event of a device failure, will indicate whether the fault lies with circuitry for the visual warning device or simply with a warning output device.