Crystal oven

About: Crystal oven is a research topic. Over the lifetime, 955 publications have been published within this topic receiving 10380 citations. The topic is also known as: oven-controlled crystal oscillator & OCXO.

Constancy on quality factor of dual-T quartz crystal resonator circuit

Abstract: In this paper, we have studied the quality factor of a dual-T quartz crystal resonator circuit of which its resonance frequency can be changed a several thousand ppm exceeding the limit of the piezoelectric coupling factor of a crystal resonator. We derived the relation between the quality factor of the dual-T circuit and the equivalent circuit parameters of the component crystal resonators. We have made the measurement and have shown that the frequency change about 1000 ppm can be obtained with constant quality factor comparable to its component crystal resonator. We made an oscillator using this dual-T circuit and also showed about 1000 ppm frequency tunability.

A Simplified Frequency Dividing Circuit

Abstract: A circuit is described in which a type 57, three-grid tube functions as two triodes in two separate oscillator circuits. One of the circuits is a crystal oscillator, and the other is a self-excited circuit which is controlled by the crystal so that it oscillates at a subharmonic of the crystal frequency.

Frequency Control Techniques for Single Sideband

Abstract: The virtual elimination of the carrier in single-side-band emission makes mandatory the accurate control of the frequencies used at the terminals of a single-sideband communications circuit. Independent, absolute frequency control of the receiver and transmitter provide immunity to propagation vagaries and interference which plague systems using partly-suppressed carrier and afc. Oscillators using high-frequency quartz resonators provide accurate and stable reference signals in small, rugged packages. A master oscillator, stabilized by phase comparison with signals derived from the reference oscillator, provide a multiplicity of accurate and stable channel frequencies.

Wellbore Instrument Clock Oscillator and Instrument System Made Therewith

Abstract: A clock oscillator includes a first crystal controlled oscillator, a second crystal controlled oscillator and a logic controller functionally coupled to the first and second crystal controlled oscillators. The logic controller is programmed to calculate a frequency of the first crystal controlled oscillator as a function of the frequency of the first crystal controlled oscillator with respect to a frequency of the second crystal controlled oscillator characterized with respect to an environmental parameter.