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Hester, H. B.

Publications and source records attributed to Hester, H. B..

Induced Environment Contamination Monitor (IECM), air sampler - Results from the Space Transport System (STS-2) flight

An investigation involving sampling the rapidly changing environment of the Shuttle cargo bay is considered. Four time-integrated samples and one rapid acquisition sample were collected to determine the types and quantities of contaminants present during ascent and descent of the Shuttle. The sampling times for the various bottles were controlled by valves operated by the Data Acquisition and Control System (DACS) of the IECM. Many of the observed species were found to be common solvents used in cleaning surfaces. When the actual volume sampled is taken into account, the relative mass of organics sampled during descent is about 20 percent less than during ascent.

Peters, P. N.

Voltage regulator dissipates minimal power and functions as a voltage divider

Regulator requires minimum amount of power for voltage division and it is not required continuously. The only power loss, except for regulating purposes, is that needed to provide for imbalances in load current requirements. For balanced loads, only leakage current flows through regulating transistors.

Hester, H. B.