DESIGN STUDY OF A TRANSISTOR CRYSTAL OSCILLATOR USING A VOLTAGE-VARIABLE CAPACITOR FOR FREQUENCY MODULATION,
Abstract
This paper presents a design study of a variablefrequency crystal oscillator and reactance modulator for use at 20 to 22 Mc in a VHF transmitter. The oscillator is essentially the transistor equivalent of the Pierce vacuum tube oscillator; however, several unusual design features are involved. In particular, a coil is used in series with the crystal in accordance with the design criteria developed here to allow stable operation over a much wider band of frequencies than is possible with an ordinary crystal oscillator. Also, the design has the output taken from a tank tuned to the second harmonic of the oscillator frequency to minimize frequency-multiplying stages. The reactance modulator employs two silicon voltage-variable capacitors connected across one capacitive branch of the oscillator. This arrangement allows the oscillator frequency to be directly deviated by an audio signal voltage. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 05, 1964
- Accession Number
- AD0451638
Entities
People
- Charles A. Fisher
Organizations
- Naval Ordnance Laboratory