Abstract: A directional object counter uses two or more light sources to generate pulses of light, which travel on two light paths across a passageway. Light from both sources illuminates two sensors, after the light has traversed the passageway, and a processor connected to the sensors determines, based on the pulsed nature of the sources, which source(s) is/are illuminating which sensor(s), and counts movement of objects through the light paths in an identified direction. The pulsed nature of the light permits low-power operation of the directional object counter with a battery. Furthermore, the independence of the pulse discrimination from the pulse generation, enables the light sources and light sensors to be positioned on opposite sides of a passageway without wiring connecting them across the passageway.

Abstract: A battery powered transmitter circuit has a LED of a continuously cycling microcomputer transmit a beam of a predetermined number of infrared pulses at predetermined time periods to a sensor of a battery powered receiver circuit. Only a clock circuit of each circuit of the same frequency is continuously powered. The two clock circuits are synchronized each time that the sensor senses the predetermined number of infrared pulses. When an object breaks the beam, the sensor causes a count of the object by a microcomputer of the receiver circuit. The receiver microcomputer is inactivated when the sensor does not sense the predetermined number of infrared pulses during one or more cycles of operation of the receiver microcomputer. There is only one count incremented on a count display after the beam is interrupted until the sensor again senses the predetermined number of infrared pulses.

Abstract: A battery powered transmitter circuit has a LED of a continuously cycling microcomputer transmit a beam of a predetermined number of infrared pulses at predetermined time periods to a sensor of a battery powered receiver circuit. Only a clock circuit of each circuit of the same frequency is continuously powered. The two clock circuits are synchronized each time that the sensor senses the predetermined number of infrared pulses. When an object breaks the beam, the sensor causes a count of the object by a microcomputer of the receiver circuit. The receiver microcomputer is inactivated when the sensor does not sense the predetermined number of infrared pulses during one or more cycles of operation of the receiver microcomputer. There is only one count incremented on a count display after the beam is interrupted until the sensor again senses the predetermined number of infrared pulses.

Abstract: A microprocessor, powered by a low cost battery, controls a wireless transmitter of a communication system. A sensor senses the value of at least one condition at a predetermined location. The transmitter transmits to a wireless receiver a data packet, which includes the value of the at least one condition, at randomly selected transmission time intervals. Closing of a multiple function push button switch activates an inactive microprocessor to cause its controlled transmitter to transmit irrespective of the selected transmission time interval until the next transmission if the switch is opened before a predetermined period of time elapses or to cause inactivation of the activated microprocessor for the longest available inactive period of time if the switch is held closed for the predetermined period of time.