Abstract: An optical assembly and electronic reader circuit cooperate to provide a highly-efficient and low-cost electro-optic barcode reader. The optical assembly includes a shielded housing, a photo detector and optical elements disposed about an un-folded optical path that provide a virtual reading window at one end of the housing whose field of view, which is focused to a point at the photo detector, is shaped to be no wider than constitutive barcode indicia. The electronic reader circuit includes a pulse amplifier and manual-adjustment-free average D.C. offset negative feedback and A.C. information peak detect negative feedback loops that respectively maintain the electrical pulse stream input to the pulse amplifier within the dynamic range thereof and eliminate electrical pulse stream peak noise. A circuit is coupled to a comparator with hysteresis square-up stage to deactivate the comparator in the state of no input signal.

Abstract: Voltage-control and current-limiting negative feedback loops are disclosed that cooperate with an adjustable voltage regulator to provide a constant-amplitude and current-limited D.C. voltage. The regulator and voltage-controlling and current-limiting feedback loops are constituted by low-cost circuit elements that cooperate to provide high-precision voltage and current regulation in a manner that is free from manual adjustment. The circuit of the invention is particularly adapted to charging lead-acid batteries.

Abstract: An optical assembly and electronic reader circuit cooperate to provide a highly-efficient and low-cost electro-optic barcode reader. The optical assembly includes a shielded housing, a photo detector and optical elements disposed about an un-folded optical path that provide a virtual reading window at one end of the housing whose field of view, which is focused to a point at the photo detector, is shaped to be no wider than constitutive barcode indicia. The electronic reader circuit includes a pulse amplifier and manual-adjustment-free average D.C. offset negative feedback and A.C. information peak detect negative feedback loops that respectively maintain the electrical pulse stream input to the pulse amplifier within the dynamic range thereof and eliminate electrical pulse stream peak noise. A circuit is coupled to a comparator with hysteresis square-up stage to deactivate the comparator in the state of no input signal.

Abstract: This disclosure is concerned with providing automatic identification of lines of time cards and the like on which time-in, time-out and related data is to be printed or recorded, by printing distinctive marks in the data field of the card on such lines, and sensing the presence of the marks to signal advancement on the next card usage to the next line.

Abstract: This disclosure is concerned with presequencing machine-readable time card identifications in the printing of decks of time cards, automatically using the time-recording clock to fill in corresponding human-readable identification, and with a correspondence map memory between machine-and-human readable identifications, enabling repetitive assignment of the machine-readable identification of subsequent decks of time cards to provide complete use of the decks by changing such assignment correspondence.