Abstract: An improved indexing key (40) for use with a circuit board connector strip (10) of the type having an elongate opening (12) for receiving the end of the circuit board and having indexing slots (22) along the top thereof spaced at predetermined intervals for receiving such indexing keys, the improved key being capable of bearing the force of the end of a circuit board being forced against it by way of compression instead of shear.

Abstract: A document containing analog data is vacuum retained on a transparent rotating drum. A data illumination head and a light responsive reading head are mounted on a carriage which moves parallel to the axis of rotation. The heads transversely scan the existing analog data as the drum rotates generating a digital new data base. The carriage is supported on air bearings that constrain movement in pitch, yaw and roll, and is driven by a precision lead screw. The sample rate of the read head is controlled by a step accumulator in response to a shaft encoder which monitors the drum rotation.