Challenging ultrasonic sensors to a performance duel, the OCB350 fluid sensor employs automatic calibration circuitry and is available with multiple output states including fluid present, no fluid present, and no tube present. Suitable for medical applications, the sensor’s setting, once calibrated, will remain constant, allowing for faster start up. Users can initiate the calibration procedure at any time by grounding the J1-pin-4, which allows remote calibration. The OCB350 consists of an infrared LED and phototransistor packaged in an opaque plastic housing that enhances ambient light rejection. An opening accommodates clear tubing with outer diameters of 1.6 mm, 3.2 mm, or 4.8 mm. The LED features a forward current of 50 mA with a peak current of 1A. Reverse voltage is 2V and power dissipation is 100 mW. The output phototransistor features a maximum collector-emitter voltage of 24V or 30V with a collector current of 50 mA and a power dissipation to 100 mW. Operating temperature range is from -40ºC to +85ºC. Typical pricing for the OCB350 is $13.15 each/1,000. OPTEK TECHNOLOGY INC., Carrollton, TX. (972) 323-2200.