Abstract: An animal actuated drinking fountain has an electronic circuit for operating a pump to supply water to an animal. The fountain has a housing with a container for holding the water. A pump receives water from the container and has an upward directed discharge port for creating a fountain of water. A light emitter and light sensor are positioned so a beam of pulsed light is positioned above the surface of the water in the container. When the animal interrupts the beam of pulsed light, electronic circuitry causes the pump to turn on and create a fountain of water for the animal to drink.

Abstract: An animal actuated drinking fountain has an electronic circuit for operating a pump to supply water to an animal. The fountain has a housing with a container for holding the water. A pump receives water from the container and has an upward directed discharge port for creating a fountain of water. A light emitter and light sensor are positioned so a beam of pulsed light is positioned above the surface of the water in the container. When the animal interrupts the beam of pulsed light, electronic circuitry causes the pump to turn on and create a fountain of water for the animal to drink.

Abstract: A system (20) for recognizing gaming chips (500) includes pairs of light emitting devices P1 through Pn, each pair emitting light (28) of a different color. The light (28) is reflected off of the surface (502) of the gaming chip (500), is sensed by a light detector (32), digitized by an analog to digital converter (33), and compared with stored intensity profiles for various denomination gaming chips (500). When a match is obtained, system (20) issues a signal indicating the color, and thus denomination, of the gaming chip (500). An energizing circuit (26) produces a constant current to ensure a constant light intensity level. An automatic adjustment circuit (40) changes the constant current to accommodate for factors such as component aging. Adjustment circuit (40) is controlled by a calibration feature wherein light (28) is reflected off of a calibration surface (42) while system (20) is in use.