Research and Development Investigation of a Precision Digital Frequency Synthesizer for SSB

摘要

A report is given concerning a research and development investigation of a low power frequency synthesizer for SSB application. An exploratory model was constructed and performance data is included. The model operates over the range of 2,000 to 32.999 Mc in L-Kc steps. Input power is approximately 1.0 watt, and minimum output power is 11 milliwatts across 47 ohms. The operating temperature range is from -40 to +70 C, and over this range the frequency stability is +3.3 x 10 to the minus 7th power. Spurious signal levels proved to be a problem at the higher output frequencies. Below approximately 15 Mc all close-in spurious were down 60 DB with harmonics down 35 DB. An analysis of the problems encountered is presented along with possible solutions for future systems. Advantages and disadvantages of single loop frequency synthesizers are also discussed. A system maintenance procedure is included for identifying and locating potential circuit malfunctions. (Author)