Solid state recording current meter conversion

Ralph T. Cheng; Lichen Wang

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Solid state recording current meter conversion

Ralph T. Cheng·Lichen Wang

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Abstract

The authors describe the conversion of an Endeco-174 current meter to a solid-state recording current meter. A removable solid-state module was designed to fit in the space originally occupied by an 8-track tape cartridge. The module contains a CPU and 128 kilobytes of nonvolatile CMOS memory. The solid-state module communicates with any terminal or computer using an RS-232C interface at 4800 baud rate. A primary consideration for conversion was to keep modifications of the current meter to a minimum. The communication protocol was designed to emulate the Endeco tape translation unit, thus the need for a translation unit was eliminated and the original data reduction programs can be used without any modification. After conversion, the data recording section of the current meter contains no moving parts; the storage capacity of the module is equivalent to that of the original tape cartridge.

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Ralph T. Cheng, Lichen Wang. 1985. Solid state recording current meter conversion. https://pubs.usgs.gov/publication/70012310

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