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Haddick, C. M., Jr.

Publications and source records attributed to Haddick, C. M., Jr..

Adaptive Telemetry Multiplexer

Telemetry-data-acquisition unit adjusted remotely to produce changes in sampling rate, sampling channels, measurement scale, and output-bias level. Functional configuration adapted to changing conditions or new requirements by distant operator over telemetry link. Reconfiguration done in real time, without removing equipment from service. Bus-interface unit accepts reprogramming commands and translates them for low-rate adaptive multiplexer. Reprogrammable equipment reduces need for spare parts, since not necessary to stock variety of hardware with fixed characteristics. Adaptive multiplexer performs well in tests, amplitude errors less than 0.5 percent, distortion less than 0.25 percent, and crosstalk and common-mode rejection indiscernible.

Sinderson, R. L.

Pogo summary report main propulsion test static firings 1-7 for shuttle development flight instrumentation

Problems concerning the shuttle main propulsion system Polar Orbit Geophysical Observatory (POGO) instrumentation and the actions taken to correct them are summarized. Investigations and analyses appear to be providing solutions to correct the majority of questionable measurements. Corrective action in the handling of cables and connectors should increase the POGO measurement quality. Unacceptable levels of very low frequency noise and data level shifts may be related to test stand grounding configuration, but further investigation is required.

Haddick, C. M., Jr.