Accession Number : AD0682675

Title :   IONIZATION IN SOUNDING ROCKET TELEMETRY TRANSMITTERS,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) RADIO AND ELECTRICAL ENGINEERING DIV

Personal Author(s) : Cairns,F. V. ; Staniforth,A.

Report Date : 29 MAR 1968

Pagination or Media Count : 7

Abstract : Rf voltage breakdown has occurred in solid state telemetry transmitters in sounding rockets on a number of occasions, resulting in a large reduction in the signal received on the ground and a loss of data. These occurrences were unexpected, since the transmitters were low power (1 watt output and 28 v dc input) and simple vacuum tests had indicated no abnormal operation. A more thorough investigation was carried out from an engineering viewpoint to find the reasons for breakdown and to devise a satisfactory remedy. It was found that transmitter breakdown could be initiated under vacuum by a glow discharge from a high dc voltage source. Tests were made with various configurations of probes, screens and electron sources to determine the type of environment required to start the breakdown. The results indicated that rf breakdown was probably caused by energetic dissociated electrons. Filling the transmitter case with a suitable dielectric material, such as minute hollow spheres of silica, was found to be a satisfactory remedy. (Author)

Descriptors :   (*SOUNDING ROCKETS, TELEMETER SYSTEMS), (*TELEMETERING TRANSMITTERS, FAILURE), IONIZATION, TELEMETERING ANTENNAS, AURORAE, FREQUENCY SHIFT, CANADA, SEMICONDUCTOR DEVICES, LEAKAGE(ELECTRICAL), GLOW DISCHARGES

Subject Categories : Atmospheric Physics
      Telemetry

Distribution Statement : APPROVED FOR PUBLIC RELEASE