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.

Quartz resonator, quartz unit, crystal oscillator, and manufacturing method thereof

Abstract: A small equivalent series resistance R n of the main vibration, crystal oscillator and their preparation with quality factor Q n value is high micro contour crystal oscillator and crystal unit and an output signal consisting of it highly stable oscillation frequency It is to provide a method. [Solution] The contour crystal resonator includes a vibrating portion, a connecting portion, and a supporting portion, which are formed by a particle method and / or a chemical etching method. Further, at least one pair of electrodes is arranged on a surface facing the vibrating portion. In addition, the contour crystal oscillator is housed in the crystal unit, and the figurine merit of the main oscillation is larger than that of the sub oscillation, and the relationship between the amplification factor of the amplifier circuit and the feedback ratio of the feedback circuit. Accordingly, a crystal oscillator whose output signal is the oscillation frequency of the main vibration can be realized with high accuracy. [Selection diagram] Fig. 1

A new type of balanced-bridge controlled oscillator

Abstract: A novel bridge-controlled crystal oscillator circuit with exceptional temperature stability is described. The contribution to the oscillator temperature coefficient of frequency (tempco) from the circuit components (exclusive of the crystal) is reduced to about 10/sup -11///spl deg/C, which is several orders of magnitude better than conventional oscillator circuits. This avoids a situation in which the overall tempco is limited by circuit component drift rather than crystal stability, which can easily occur with conventional circuits when the crystal is ovenized at a turnover point. Previous attempts to use a bridge in an oscillator were made by Meacham (1938), who used an imperfectly balanced bridge, and Sulzer (1955), who used a balanced pseudo-bridge. The reasons why these are unsatisfactory are discussed. Although the bridge greatly reduces reactive frequency pulling, it does not address directly the additional issue of pulling caused by variations in crystal drive current amplitude. However, it is an enabling technology for a novel ALC circuit with greatly improved stability. The new bridge-controlled oscillator is also much less sensitive to other environmental effects such as humidity (2/spl times/10/sup -11/, 5%/25% R.H. @70/spl deg/C), power supply voltage, load impedance, and stray capacitance.

Frequency modulated crystal controlled oscillator operable at a plurality of temperature compensated center frequencies

Abstract: A frequency modulated, solid state, crystal controlled oscillator, including a voltage variable capacitor, for use in portable transmitters wherein it is desired to operate at a plurality of center frequencies that are stable with temperature change. Any one of a plurality of center frequency determining circuits, each including a crystal operating in its parallel resonant mode, can be selected to determine a desired center frequency. Each crystal is connected in parallel with a temperature compensating network. The biasing point of the voltage variable capacitor, the net inductance of a circuit which applies the modulating voltage thereto are selected to cause the nonlinear characteristics of the crystal and voltage variable capacitor to counterbalance each other so that linear modulation is attained.