FREQUENCY-ERROR INDICATOR FOR MULTIPLEX TELETYPE SIGNALS.
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)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 05, 1967
- Accession Number
- AD0664654
Entities
People
- B. A. Tretick
- D. A. Venn
- L. M. Leibowitz
Organizations
- United States Naval Research Laboratory