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Airoscope command systemA PCM telemetry command system is presented having a capacity of 256 unique commands, an end-to-end actuation time of less than 250 milliseconds, and an address plus complementary command code to provide security against the acceptance of anything but intended commands. The system consists of a ground-based encoder and a balloon-borne decoder, both built using low-current drain, high reliability CMOS logic elements. Commands are normally issued by a simple switch closure to +5VDC on the appropriate input line, however as a backup mode, the 8-bit command may be entered manually on 8 toggle switches and executed via a SEND button. In any case, the command is then serialized into a PCM bit stream and sent via a P-Band radio link to the DECODER aloft. All 256 outputs from the DECODER are buffered through drivers and thus may be used to drive CMOS, TTL, or DTL logic.
Document ID
19750004691
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Barrows, W.
(NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
August 8, 2013
Publication Date
November 1, 1974
Publication Information
Publication: Telescope Systems for Balloon-Borne Res.
Subject Category
Communications And Radar
Accession Number
75N12763
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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