Accession Number : AD0664654

Title :   FREQUENCY-ERROR INDICATOR FOR MULTIPLEX TELETYPE SIGNALS.

Descriptive Note : Phase I of interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Venn,D. A. ; Leibowitz,L. M. ; Tretick,B. A.

Report Date : 05 DEC 1967

Pagination or Media Count : 12

Abstract : The need for highly accurate, precise, and rapid frequency monitoring of Naval communications circuits and systems has led to the development of a new technique for on-line determination of the frequency of each tone of a 16-channel frequency-shift keyed (FSK) multiplex (MUX) teletype signal to within 1 hertz (Hz). Frequency mixing and filtering, in combination with precise digital timing and counting circuitry, is used to generate a start-stop pulse for time interval measurement. A counter utilizing the output of the monitor and high-frequency input from a precise frequency standard for reference provides instant display of MUX tone frequency for determination of frequency error and other supervisory purposes. (Author)

Descriptors :   (*NAVAL OPERATIONS, COMMUNICATION AND RADIO SYSTEMS), (*TELETYPE SYSTEMS, MONITORS), MULTIPLEXING, FREQUENCY, ERRORS, COUNTING METHODS, DIGITAL SYSTEMS, NAVAL EQUIPMENT, CIRCUITS, FREQUENCY SHIFT, FREQUENCY SHIFT KEYERS

Subject Categories : Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE