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    Apollo Command Module Environmental Control System Hardware: Two Steam Duct Pressure Switches, AiResearch Part 836114 (Contract NAS-9-150). Each metal box, 4.125" (overall) x 1.5" x 2.75", has multi-pin electrical and screw-on pressure connectors on one end with a red "Warning/ Dielectric/ Testing/ Completed" sticker. A metal ID plate along one side presents the following data: "Consolidated Controls Corp./ Bethel Connecticut/ Switch, Pressure/ CCC Part No. 21PA6-2/ Date of Mfg. 7/66/ Mfg'd for Airesearch Per 836114-1-1/ [Serial No] 0009809/0009810". Included are several pages copied from a 1973 abstract prepared by AiResearch for the NASA MSC titled "Environmental Control System Transducer Development Study". It reads, in part: "The back pressure transducer was implemented in the initial stages of Apollo ECS as an obsolute pressure switch that sensed the pressure in the glycol evaporator steam discharge duct. The transducer functioned as a safety device to prevent the steam discharge pressure from falling below 5 mm Hg. The requirement of this transducer in the Apollo Block II ECS was eliminated, and the production of this transducer was discontinued." Both very fine.

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    Auction Dates
    May, 2015
    22nd Friday
    Internet/Mail Bids: 8
    Lot Tracking Activity: N/A
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