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.

Temperature compensation circuit for a crystal oscillator

Abstract: A temperature compensation circuit (10) for a crystal oscillator module (12) used in a communication device (200). An existing microcontroller (210) of the communication device (200) is used to provide temperature compensating digital data (30) for a crystal oscillator (18). In this way, the crystal oscillator module (12) does not require an on-board memory which substantially cuts costs. The temperature compensation digital data (30) is converted to a temperature compensation signal (22) in a digital-to-analog converter which controls the crystal oscillator frequency. However, typical digital-to-analog converters are driven by voltage regulators which vary over temperature. To solve this problem, the crystal oscillator module (12) includes an on-board voltage regulator (34) which supplies a characterized regulated voltage (36) to the digital-to-analog converter such that the temperature compensation signal (22) from the digital-to-analog converter is inherently corrected for voltage variations in the voltage regulator (34). This improves stability of the output frequency (20) from about 5ppm to about 2ppm.

Enhanced clock based on the Chip Scale Atomic Clock and Dual-Mode Crystal Oscillator

Abstract: In this paper we introduce enhanced low power clock system that is able to achieve frequency stability ±001 ppm over a wide temperature range, which is approximately 100 times better than the stability achievable with typical Temperature Compensated Crystal Oscillator (TCXO) The proposed clock system is based on Dual-Mode Crystal Oscillator (DMXO) and the Chip Scale Atomic Clock (CSAC) Power consumption of the clock system is comparable with the power consumption of the CSAC (Symmetricom SA45s) in the low power mode Typical power consumption of the CSAC is approximately 120 mW in a normal full accuracy mode (±001 ppb) In the low power mode, the CSAC operates as simple TCXO and consumes less than 20 mW of power; however over a wide temperature range, the frequency stability is limited to ±1 ppm

A Quartz Servo Oscillator

Abstract: The paper deals with a 5 mc oscillator whose frequency instabilities due to vacuum tube effects are at least 100 times less than those present in the best conventional oscillators which achieve stabilization by resonant vector balance. By using quartz crystals of low drift, it is therefore possible to reduce unpredictable frequency changes to one or two parts in 1010. The tubedependent instabilities in conventional oscillators are reviewed, the conclusion being that even with circuit Q values as high as 2 million it is not possible to guarantee frequency instabilities as low as 10-9, much less 10-10. A plan for dual stabilization by resonant-loop balance and bridgeoperated servo to one part in 1010 is described. The development of an oscillator based on this plan and intended as a working frequency standard is explained with the aid of block diagrams and performance data.

A miniaturized precision time source for use in self-contained instruments,

Abstract: : A miniaturized precision time source for use in self-contained instruments was designed and constructed. This instrument was devised expressly to provide a precision time base for the submersible pingers now used at the Woods Hole Oceanographic Institution. The device employs a 100 kc per second crystal as its frequency standard, a silicon transistor oscillator stage, a germanium transistor buffer stage, and five silicon unijunction transistors as decade frequency division stages. It is stable over the entire range of temperatures found in the ocean. The output consists of a positive pulse occurring at one second intervals and at a voltage level adequate for direct application to a cold cathode trigger tube. The frequency stability is better than two parts per million per degree centigrade as determined by the temperature coefficient of the quartz crystal presently employed, which is operating at ambient temperature. The point to point jitter is less than one part per million. (Author)