Accession Number : ADP002448

Title :   Microprocessor for the NR Series of Hydrogen Maser Frequency Standards,

Corporate Author : JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB

Personal Author(s) : Mengel,E. E. ; Stover,D. W.

Report Date : 1983

Pagination or Media Count : 5

Abstract : The NR series of hydrogen maser frequency standards was designed by the Applied Physics Laboratory with funding and direction supplied by NASA Goddard Space Flight Center for use in the crustal dynamics investigations. In order to develop a high level of confidence that hydrogen masers were performing throughout extended weeks of field experiments, a microprocessor monitor and control system has been incorporated into the NASA-NR model hydrogen masers. This system provides control of the resonant frequency of the cavity, synchronization of the clock output, and a data link for archiving the vital performance characteristics of the maser that can be added to the data base for VLBI data processing. The monitoring and remote command features provide diagnostic information for preventative maintenance and control to set any of the maser operating parameters. The monitoring information can be observed at the local site and via phone/modems at remote locations as well. The flexibility that the microprocessor provides allows the maser frequency standard to become a complete, self-contained time and frequency instrument.

Descriptors :   *Frequency standards, *Masers, Hydrogen, Microprocessors, Frequency, Hydrogen, Monitoring, Time, Resonant frequency

Distribution Statement : APPROVED FOR PUBLIC RELEASE