Abstract: A light is dimmed by pulsing it at a selected duty cycle. By pulsing, the light can be dimmed without being turned off completely which reduces wear on the filament. The circuit is designed for flashing a pair of ditch lights on a railroad locomotive. The lights are alternately illuminated at full voltage and dimmed by pulsing. The flashing sequence can be activated when the locomotive is travelling below a selected speed or when the horn is sounded. The duration of the flashing sequence is controlled by a timer. The pulsing circuit can be used to effectively reduce a voltage without voltage dropping resistors.

Abstract: A light is dimmed by pulsing it at a selected duty cycle. By pulsing, the light can be dimmed without being turned off completely which reduces wear on the filament. The circuit is designed for flashing a pair of ditch lights on a railroad locomotive. The lights are alternately illuminated at full voltage and dimmed by pulsing. The flashing sequence can be activated when the locomotive is travelling below a selected speed or when the horn is sounded. The duration of the flashing sequence is controlled by a timer. The pulsing circuit can be used to effectively reduce a voltage without voltage dropping resistors.

Abstract: Heaters are used to simulate wheel bearings at specified temperatures. Two heaters are mounted on each side of a railroad test car. The heaters are mounted on the sprung carriage of the car to reduce vibration of the hardware and avoid interfering with wheel trucks on the car. Ambient temperature sensors are similarly mounted. Wire brushes are mounted below the heaters and sensors to activate magnetic wheel flange sensors. The heaters are controlled by a system which is integrated with a hot wheel simulator system.

Abstract: A simulator is provided for verifying the proper operation of railroad rolling stock hot wheel detectors. The simulator includes heaters mounted on trucks of a railroad car, between the wheels and within the profile of the thickness of the wheels. Shock mounts, spring mounts and safety cables are used. An electromagnet is mounted on the heater to trip a sensor to activate the detector and a sensor on the car is used to determine the ambient temperature. Each heater includes a heater temperature sensor and is maintained at a constant temperature above ambient to approximate the thermal radiation of a hot wheel. Each heater is adjusted to direct heat horizontally outwardly from the truck to permit a hot wheel detector adjacent to and outside of the rail to detect a hot wheel. The car has two trucks with one heater on each side of each truck. One heater on each side simulates a temperature approximately equal to a hot wheel.

Abstract: The self-contained diagnostic system is provided for a stroboscopic light circuit. The diagnostic system includes a plurality of signal lights, preferably LEDs, connected at various locations in the circuit to provide a visual indication of the faulty portion of the circuit in the event that the circuit does not operate properly. The system provides a quick and easy method for determining the location of a malfunction of a stroboscopic light without the necessity of replacing the entire light system or the use of diagnostic equipment.