Abstract: An apparatus for providing an optical code reading mode and a data communication mode comprises an optical detector, a variable-gain amplifier having an input and an output, an optical code reader circuit and a data communication circuit. The input of the variable-gain amplifier is responsive to the optical detector. The optical code reader circuit and the data communication circuit are responsive to the output of the amplifier. The variable-gain amplifier provides a first gain during the optical code reading mode, and a second gain during at least a portion of the data communication mode, wherein the second gain is less than the first gain.

Abstract: A device for collecting substances for testing comprises a vial having a first, generally open end, engageable by a removable closure member, and a second, generally closed end. A removable closure member is provided having first and second ends. The first and second ends of the closure member are engageable with the first end of the vial. An absorbent member is preferably attached to the removable closure member and is receivable in the vial whereby the absorbent member is located outside of the vial prior to use, with the first end of the vial being secured to the second end of the closure member to provide a handle, and after use, the second end of the closure member is removed from the first end of the vial, the closure member is inverted, the absorbent member is inserted into the vial and the first end of the closure member is removably engaged to the first end of the vial.

Abstract: An electrostatic aperture printer employing a gating mask placed between a source of ions and a charge receiving member to generate imagery consisting of aggregations of elemental dots or line segments formed in response to electronic control signals wherein the improvement lies in electrically biasing the mask or mask segments in such a way that the functions of ion collection and control are combined in the region between the mask and a charge receptor backing electrode via the establishment of appropriate transmission or blocking fields. Further electrostatic printing improvements incorporated are the development of useful charge receptor holddown forces via static or rolling backing electrode structures designed to make constructive use of the longitudinal tension normally developed in receptor web handling, and enhanced ion transmission achieved by means of shaped aplanar mask structures incorporating zones fabricated from insulating material.