Abstract: The oscillator circuit comprises an amplifier having a pair of inputs, a positive feedback path producing a positive feedback ratio to one of the inputs, and a negative feedback path including a series resonant circuit producing a negative feedback ratio to the other of the inputs. The positive and negative feedback paths are independent such that the current in each of the paths can be adjusted independently. In this manner, a high Q multiplier effect is achieved. Also, the circuit has an output path which is separate from the input path so that a high output signal level can be achieved while maintaining a low current through the series resonant circuit.

Abstract: A high frequency oscillator is provided by connecting two amplifier circuits in parallel where each amplifier circuit provides the other amplifier circuit with the conditions necessary for oscillation. The inherent noise present in both amplifier circuits causes the quiescent current, and in turn, the generated frequency, to change. The changes in quiescent current cause the transconductance and the load impedance of each amplifier circuit to vary, and this in turn results in opposing changes in the input susceptance of each amplifier circuit. Because the changes in input susceptance oppose each other, the changes in quiescent current also oppose each other. The net result is that frequency stability is enhanced.

Abstract: A VCO including an oscillation sustaining feedback loop for maintaining the phase shift between the output and the input of a first amplifier to sustain oscillations. A diversion gate coupled with the input of the first amplifier causes the frequency of oscillation to be adjusted by introducing a phase shift within the feedback loop to thereby force the resonant frequency of a crystal connected to the input of the first amplifier to change accordingly. The feedback loop comprises a first integrator connected to the output of the first amplifier, a second amplifier having an input coupled to the output of the first amplifier and an output coupled to the input of the first amplifier and a second integrator connected to the output of the second amplifier with the output of the diversion gate being connected to the output of the second amplifier.

Abstract: The invention concerns a very high frequency quartz oscillator. The feedback loop of the oscillator comprises a compensation network of a quartz at the frequency of the oscillator, and a low-pass filter eliminating the frequencies lower than that of the oscillator. A power divider having two branches allows to send the signal issuing from the feedback loop, on the one hand, to the amplifier input of the oscillator and, on the other hand, to the output amplifier. Two-port networks Q.sub.1 to Q.sub.6 match the impedances at the input and at the output of the amplifier of the oscillator, of the feedback loop and of the output amplifier.

Abstract: A voltage controlled oscillator having an electrical means of frequency control which is able to operate from a supply voltage which is lower than is desirable to use with a "VARICAP" diode. The oscillator comprises a pair of transistors whose base and collector electrodes are connected together, the base electrodes being connected to a supply rail and the collector electrodes are connected to a tunable parallel LC resonant circuit. A frequency determining device, e.g. a crystal, is connected between a tapping of the resonant circuit and the emitter of one of the transistors to form a first feedback path. The crystal together with an integratable small value capacitor connected between the emitters of the two transistors form a second feedback path. The phase shifts due to the first and second feedback paths are summed vectorially at the collectors of the two transistors. By varying the gain of each of the two transistors then the resultant phase shift, and thereby the frequency of oscillation, are varied.

Abstract: A direct frequency modulation crystal-controlled oscillator circuit is provided having a configuration which minimizes the number of parts required for modulation while maintaining a linear relationship between the incoming modulation voltage and the outputted frequency. The circuit includes a tuning diode in a parallel arrangement with a tank circuit connected to the collector of a transistor. In the preferred embodiment, the tank circuit includes only an inductor. The crystal of the circuit operates in the anti-resonant mode and its impedance is much greater than that of the tank circuit. Direct frequency modulation results from the frequency change of the crystal in responding to a phase change caused by the modulation voltage applied to the tuning diode, which subsequently results in a change in the phase of a transistor collector voltage.

Abstract: A television signal generator for producing a composite RF signal without high level intermodulation products. A signal network is provided to linearly combine a first video modulated carrier signal and a second carrier frequency of the same frequency modulated with an audio modulated subcarrier. An audio subcarrier generator is disclosed having a ceramic resonator for a frequency determining circuit element. The resonator is parallel connected with a voltage sensitive reactance element to provide a frequency modulated subcarrier in response to a modulating voltage.

Abstract: A piezoelectric oscillator operating in the aperiodic or overtone mode comprising a first piezoelectric resonator having a resonance frequency at which the oscillator is to operate. One side of the first resonator is connected to ground, and the other side is connected through a second piezoelectric resonator to the base of a transistor. The second resonator has in common with the first resonator a mode at the resonance frequency, but its intrinsic quality factor is between 30 and 1000 times smaller than that of the first resonator. A capacitive divider bridge having a middle point is connected between the base of the transistor and ground. A third piezoelectric resonator having in common with said first resonator a mode at said resonance frequency, but whose intrinsic quality factor is of the same order of size as that of the second resonator, is connected between said middle point and the emitter of said transistor.

Abstract: A device having the function of compensating for the acceleration sensitivity of an oscillator of given nominal frequency comprises an acceleration-sensing element such as a filter which is capable of producing a signal having a nominal frequency equal to that of the oscillator to be compensated but, in respect of its nominal frequency, has higher sensitivity to acceleration than the oscillator to be compensated. The phase difference between the frequency of the oscillator and the frequency produced by the filter is compared in a mixer in order to extract the phase modulation induced by the acceleration. A follow-up control amplifier receives the output signal of the phase comparator and produces at its output a signal for correcting the oscillator.

Abstract: A crystal oscillator circuit that is temperature compensated over a broad temperature range has a crystal oscillator, a reactance compensation circuit for providing temperature compensation at low temperatures, and a control voltage-generating circuit for providing temperature compensation at high temperatures. The reactance compensation circuit includes the parallel combination of a thermistor and a variable-capacitance diode, and this parallel combination is connected in series with the crystal oscillator. The control voltage-generating circuit includes a thermistor and transistors and applies a voltage corresponding to the ambient temperature to the variable-capacitance diode of the reactance compensation circuit.

Abstract: An oscillator circuit for sensing and indicating temperature by changing oscillator frequency with temperature comprises a programmable operational amplifier which is operated on the roll-off portion of its gain versus frequency curve and has its output directly connected to the inverting input to place the amplifier in a follower configuration. Its output is also connected to the non-inverting input by a capacitor with a crystal or other tuned circuit also being connected to the non-inverting input. A resistor is connected to the program input of the amplifier to produce a given set current at a given temperature, the set current varying with temperature. As the set current changes, the gain-bandwidth of the amplifier changes and, in turn, the reflected capacitance across the crystal changes, thereby providing the desired change in oscillator frequency by pulling the crystal.

Abstract: An oscillator comprises an amplifier with a feedback loop from the output to the input thereof, the feedback loop including a resonator such as a crystal providing oscillation of the amplifier at a predetermined frequency. A balanced modulator coupled to the amplifier generates a voltage varying at the same frequency, said voltage being selectably variable in amplitude from zero upward either in phase with the amplifier or 180 degrees out of phase therewith. The voltage is selectably inserted into the feedback loop 90 degrees out of phase with the output of the amplifier, whereby, when it is inserted, the frequency of oscillation of the amplifier varies from the predetermined frequency in direction depending upon the phase relationship of the amplifier and voltage and in amount upon the amplitude of the voltage.

Abstract: A piezoelectric oscillator of the Clapp type for operation in the overtone mode comprises a piezoelectric resonator having a C-mode resonance frequency at which the oscillator is designed to operate, the resonator being connected between the base of a transistor and ground. A capacitive voltage-dividing bridge is also connected between the base of the transistor and ground, the so-called midpoint of the bridge being connected to the emitter of the transistor. A quartz crystal and an inductance coil decoupled by a capacitor are placed between the emitter of the transistor and ground. The inductance coil and the capacitor form a high-pass filter for attenuating frequencies below the resonance frequency. The piezoelectric resonator is tuned to the mode B which is adjacent to the mode C in order to eliminate the unwanted mode B.

Abstract: A low power, fast start up time crystal oscillator circuit has an amplifier portion powered from a one cell battery. The input stage of the amplifier portion is a common emitter amplifier circuit. A second stage includes a dual collector current mirror circuit having a current established at 3 times the input stage current. The output stage includes a current mirror circuit having a current established at 4 times the second stage current. A negative D.C. feedback circuit biases the amplifier portion. A single transistor interface circuit boosts and limits the output of the amplifier portion and permits the oscillator to drive other circuits that operate at higher voltages than the amplifier battery voltage.

Abstract: A low current oscillator/buffer amplifier configuration is disclosed which provides a simple, inexpensive, low power oscillator with reduced harmonic output. Buffer 60 is coupled to the resonant tank circuit 58 of oscillator 50 by means of impedance transform network 70. This technique of tapping directly from the tank provides a buffered output signal having low harmonic content. Furthermore, impedance transform network 70 permits coupling feedback amplifier 52 to buffer amplifier 62 in a totem-pole amplifier stage configuration. This feature provides a significant current savings over conventional oscillator/buffer circuits. The instant invention is particularly well adapted for use as reference frequency oscillators in portable radio applications.

Abstract: A multi-channel frequency synthesizer, including a crystal oscillator circuit that may be selectively operated to provide a reference signal at a selected reference frequency that is one of a given plural number of frequencies; an IF generator for processing the reference signal to provide an IF signal at a selected intermediate frequency that is one of a given plural number of submultiples of the selected reference frequency; a comb generator for processing the reference signal to provide a comb of signals separated from each other by the selected reference frequency; and a phase-locked loop.

Abstract: In an apparatus having an insulative substrate, a power circuit is mounted on one surface of the substrate and connected to receive power from a mains supply for rectifying the AC energy of the supply and supplying the rectified energy to a pair of power lines. A high frequency source is mounted on the same surface as the power circuit and electrically connected to the power lines for converting the rectified energy into oscillation energy. A shield casing, which is electrically connected to one of the power lines which is lower in impedance than the other, encases the high frequency source. A conductor, printed on the other surface of the substrate, is substantially aligned with a portion of the shield casing which is positioned between the power circuit and the high frequency source, the conductor being electrically connected to the power line having the lower impedance to suppress radiation which would otherwise leak through a gap between the shield casing and the substrate.

Abstract: A variable frequency oscillating circuit of the general Colpitts kind in which the frequency of oscillation varies in accordance with the current in a constant current source and oscillation stability is high because the oscillator is of the general LC form. Resonance is provided by a solid-state resonator driving a transistor forming the Colpitts oscillator and which is connected to ground through a constant current source having a controllable current to set the frequency of oscillation. The response characteristic can be linearized using a compensating circuit employing additional constant current sources and current mirror circuits.

Abstract: An electronic drive circuit for driving an actuator mass for a sensor apparatus is disclosed. The driver requires no compensation or bridge elements. The actuator mass is directly driven by a square wave drive signal such that all of the capacitors loading errors associated with the driven actuator means are concentrated in time to that time interval in which the drive signal traverses between its two stable states. A sensor circuit connected to monitor the sensor output response signal is blanked out during the drive signal transition time interval, which effectively eliminates the transition drive noise energy from the sensed output signal.

Abstract: A high-frequency oscillator including an oscillation circuit (1) having a quartz crystal (X) and an amplifying element (Q.sub.2), a power amplifying circuit (3) for amplifying the output of the oscillation circuit, and a control system (Q.sub.7, 6) for varying a bias voltage of the amplifying element to thereby control the output power of the power amplification circuit. The control system comprises an FET (Q.sub.7) connected at the drain thereof to the amplifying element, and a control circuit (6) for applying a control signal to the gate of the FET.

Abstract: The high frequency oscillator includes a piezo-electric crystal (1) which is connected to at least two exciter electrodes (3, 4) and means which make it possible to apply on the one hand to the electrodes (3, 4) electric excitation power for the crystal according to a useful vibratory mode which is selected to determine a frequency reference, and on the other hand additional electric power for exciting the crystal according to an overtone vibratory mode which is distinct from the useful vibrational mode. Means (46, 47) are also provided to regulate the electric excitation power of the crystal according to the useful vibratory mode in a predetermined and constant proportion in relation to the additional electric power. The invention makes it possible to compensate, using the isochronism deficiency stemming from the additional vibration on the useful mode, the indirect amplitude-frequency effect stemming from the additional vibration, and vice versa.

Abstract: A crystal oscillator, including two crystals of unequal acceleration sensvity magnitude and mounted such that their respective acceleration sensitivity vectors are aligned in an anti-parallel relationship, further includes at least one electrical reactance, such as a variable capacitor, coupled to one of the crystals for providing cancellation of acceleration sensitivities. After the acceleration sensitivity vectors of the two crystals are aligned anti-parallel, the variable capacitor is adjusted until the net or resultant acceleration sensitivity vector of the pair of resonators is reduced to zero. A second electrical reactance, such as a variable capacitor, is utilized as a tuning capacitor for adjusting the oscillator's output frequency to the desired value, while maintaining the cancellation of acceleration sensitivities.

Abstract: Between insulative layers (31-37, 41-44), a multilayer substrate comprises at least one dielectric layer (26-29). It is possible to form capacitors (58), resistors (46), and wiring conductors (61, 62) in the substrate. The at least one dielectric layer should be of at least one dielectric composition which has a perovskite structure. Preferably, each insulative layer is of an insulating material which consists essentially of aluminum oxide and lead borosilicate glass. The substrate is convenient in manufacturing a crystal oscillator by mounting a crystal vibrator (71) and a transistor (72) on the principal surface(s). Examples of the dielectric composition are:Pb[(Fe.sub.2/3.W.sub.1/3).sub.0.33 (Fe.sub.1/2.Nb.sub.1/2).sub.0.67 ]O.sub.3,Pb[(Mn.sub.1/3.Nb.sub.2/3).sub.0.01 (Mg.sub.1/2.W.sub.1/2).sub.0.30 (Ni.sub.1/3.Nb.sub.2/3).sub.0.49 Ti.sub.0.20 ]O.sub.3,andPb[(Mg.sub.1/2.W.sub.1/2).sub.0.66 Ti.sub.0.34 ]O.sub.3.

Abstract: Oscillator circuit comprising an amplifier arrangement being connected to a reference level an output and an input thereof being coupled via a single signal-carrying terminal to a resonant network which is connected to the same reference level as the amplifier arrangement, the resonant network comprising a crystal resonator. A stable oscillation at a higher order crystal resonant frequency is provided by means of an LC-network which selects said higher order crystal resonant frequency and a resistor connected in parallel across the crystal resonator, which prevents parasitic oscillations at the resonant frequency determined by the components of the LC-network and the case or holder capacitance of the crystal resonator.

Abstract: The invention relates to a crystal controllable oscillator circuit. The oscillator includes an amplifier and an oscillation sustaining feed-back loop coupled between an output and an input of the amplifier the loop including two integrators in series for inhibiting oscillation at crystal overtones. Each integrator provides 90.degree. phase shift independently of the oscillators defining RC product which determines only the gain thereby making the oscillator less sensitive to variations in circuit time constants due to temperature and manufacturing tolerance effects. The invention is particularly suitable for incorporating in integrated circuit form where only a single pin connection is required for the controlling crystal.

Abstract: An oscillator circuit utilizing multiple (two) quartz crystal resonators as the frequency controlling elements in a novel circuit arrangement. The use of two crystal units increases the oscillator circuit signal transmission group delay by a factor of 2 to 3 and effects an estimated 6 dB reduction in oscillator output signal phase noise sideband level at carrier offset frequencies less than the resonator half-bandwidths. The degree of resonator tracking required is made practical with the use of temperature controlled SC-cut resonators. In addition, the oscillator circuit is configured so that equal, correlated output signal currents can be extracted from each resonator through individual load circuits, thereby increasing available oscillator output signal amplitude by 2:1 and reducing the net effect of uncorrelated load circuit additive noise by 3 dB.

Abstract: A method for flating the phase characteristic of a differential detection signal in one higher and lower regions thereof relative to its resonance frequency by controlling a differential characteristic. A searching, over a range, which is wider than the width of the flat region, is accomplished prior to phase characteristic being effected thereby discriminating a fundamental resonance frequency. After this discrimination of the fundamental resonance frequency, automatic tracking is effected under stable corrected phase characteristics for the fundamental resonant frequency whereby high electro-mechanical conversion efficiency can be maintained.

Abstract: An oscillation circuit has a free-running oscillator operating at a predetermined frequency. A signal generator generates a trigger signal in synchronism with an input signal. The trigger signal is supplied to the free-running oscillator to bring the signal level in the oscillator to a reference level. The oscillator keeps its frequency even when there is no input signal, the frequency being approximately equal to an integer multiplied by the frequency of the input signal.

Abstract: A standard TTL inverter (1) drives a series circuit of an inductor (9) and a capacitor (11). This is fed back through a frequency-control crystal (15). A resistor (19) is also in the feedback circuit, and a resistor 7 bridges the low-current-accepting inverter (1). None of the circuit elements need be of high precision or otherwise expensive.

Abstract: A temperature compensated crystal oscillator in which the base emitter voltage of transistors in an integrated circuit is used to provide substantially linearly temperature sensitive outputs which are employed to generate a series of polynomial functions of Chebyshev-like form which are summed and used to control a varicap diode in the oscillator feedback path.

Abstract: To increase the gain and, consequently, to increase the voltage amplitude appearing at the crystal of a crystal oscillator a conventional circuit including a first differential amplifier in the amplifier section and two further differential amplifiers in the phase shifting section is modified to include a fourth differential amplifier in the amplifier section. The fourth amplifier carries an additional current to flow in the two differential amplifiers causing an additional current to flow and across the operating resistance of the two differential amplifiers an additional voltage drop being fed to the crystal via an emitter follower.

Abstract: A temperature-compensated quartz oscillator having a first plate of quartz that carries a first electrode which displays a sensitivity to temperature that exceeds that of the piezoelectric quartz wafer which comprises a first resonator which vibrates at a reference frequency f.sub.M. The first plate cooperates with the first electrode and a third electrode to form a second quartz resonator. Means for applying to the first and third electrodes an excitation electric power to drive the active portion of the first plate according to a mode which is sensitive to temperture, at a frequency f.sub.T close to, but slightly different from, the reference frequency f.sub.M. Means for comparing, which enable comparison of signals at the terminals of the second and third electrodes, and control means for the regulating means for applying an excitation electric power from the active portion of the piezoelectric wafer.

Abstract: A narrow band, voltage controlled crystal oscillator having a linear frequency versus tuning voltage response. The oscillator uses a composite resonator in a novel circuit configuration with a resulting improvement in oscillator output signal frequency stability.

Abstract: An oscillating circuit includes first and second stage amplifiers, a feedback circuit formed of a capacitor and a resistor and connected between the output terminal of the second stage amplifier and the input terminal of the first stage amplifier and a crystal resonator having a predetermined resonance frequency and being connected to the first stage amplifier, the total gain of the oscillating circuit being selected so that the oscillating circuit initiates its oscillation only when the crystal resonator is connected to the first stage amplifier.

Abstract: Two oscillators are utilized to convert digital data into an FSK modulated signal. One oscillator is at the mark frequency and the other is at the space frequency. FSK modulation is accomplished by switching between the two frequencies based on the state of the digital data. Phase and frequency shifting techniques are also provided to insure that a desired difference between the mark frequency and space frequency is maintained and to also insure that a proper phase relationship is maintained between the output from the two oscillators.

Abstract: The subject of the invention is a high frequency bandpass amplifier with adjustable impedance, in particular for a high frequency quartz resonator. It includes a transistor T connected in common base the emitter of which is connected to ground by a resistive divider bridge (R.sub.2, R.sub.1) the mid-point of which forms the input of the amplifier. The collector of the transistor (T) is connected to ground by a parallel circuit (LC) having one inductive side (L) and one capacitive side (C), a mid-point of the inductive side (L) or of the capacitive side (C) forming an output (s.sub.1 or s.sub.2) of the amplifier (A). The base of the transistor is biased and connected to ground via a capacitor (C.sub.3) ensuring common base operation in the pass-band of the amplifier. The invention also relates to an oscillator of transmission type including such an amplifier and a resonator (1) connected between the input (e) and one output (s.sub.1 or s.sub.2) of the amplifier (A).

Abstract: A crystal oscillator comprises an active coupling member driving the series mode resonance of a piezoelectric crystal proportionally to a feedback voltage. Said coupling member is followed by a current boosting transformer whose secondary winding is connected to an output amplifier and to a clipping amplifier shunted across said secondary winding and itself followed by a band-pass filter which supplies said feedback voltage to said coupling member.

Abstract: A single-crystal oscillator comprising a single transistor and a capacitor divider connected in a feedback path, which includes the crystal input and output ports, between the collector and base of the transistor, thereby to provide a low-impedance input port to the crystal. The impedance of the crystal output port, which is connected to the base of the transistor, is also low. As a result of the low crystal input and output port impedances, the oscillator is capable of operating without any significant levels of spurious crystal frequencies, and can be switched between crystal and voltage-controlled modes of operation without frequency pull or lock-up to the crystal when operating in the voltage-controlled mode.

Abstract: An amplitude modulation circuit wherein a resonant circuit for the determination of the carrier-wave frequency is connected to the collector of one transistor forming a differential pair of transistors forming a differential amplifier having its ground terminal connected to a constant current source while an output terminal of the resonant circuit is coupled to the base of the other transistor forming the differential pair so as to apply a positive feedback to the other transistor thereby forming a carrier wave oscillating circuit, and a constant current adjusting means for dividing by switching the current to be supplied to one of the transistors of the differential pair is connected between the differential amplifier and the constant current source, such that, by supplying a modulating signal to the constant current adjusting means to vary the oscillating level of the carrier wave, a modulated signal at a constant modulation degree can be obtained from the base of the other of the transistors forming the di

Abstract: A high-frequency negative resistance circuit for use in a voltage controlled crystal oscillator has a pair of input terminals thereby defining an input current and input voltage. The high-frequency negative resistance circuit includes a sensing circuit for sensing the input current, a biasing voltage source and a load impedance connected to the voltage source. The high-frequency negative resistance circuit further comprises a current mirror circuit connected to the sensing circuit and to the load impedance for producing a current in the load impedance. The current in the load impedance is approximately equal to the input current. The current mirror circuit also controls the sensing circuit to cause the input voltage to decrease as the input current increases. Decreasing input voltage with increasing input current defines the negative resistance. When this negative resistance circuit is configured with a crystal and a voltage controlled capacitance, an oscillator capable of high-frequency operation results.

Abstract: The invention relates to a quartz oscillator comprising two transistors to whose base terminals the collector voltage of each one of the other transistors is applied, a two-terminal network incorporating a quartz resonator being connected to the emitter of one of the transistors. The collector voltage is applied to the corresponding base via a semiconductor junction. The oscillator further includes respective emitter and collector impedances for the transistors in which the product of the emitter impedances is greater than the product of the collector impedances. When the supply voltage is sufficiently low so that the collector-base diodes of the transistors are always in the non-conducting state, the oscillator frequency is independent, to a very large degree, of saturation phenomena of the two transistors. When manufactured in integrated circuit form, only one additional exterior terminal is required for the connection of a quartz resonator.

Abstract: An integrated crystal voltage controlled oscillator (VCO) with only two terminals for the crystal network and no additional terminals for decoupling, bypass capacitors, etc., as well as no internal capacitors is disclosed. A negative feedback loop having both AC and DC gain for increased amplification stability as well as a separate positive feedback path having little or no DC gain but sufficient AC gain at the desired oscillating frequency to compensate for the negative feedback are provided in the crystal VCO which is capable of low voltage, e.g., 5 VDC, and high frequency, i.e., greater than 10 MHz, operation and thus is particularly adapted for digital applications utilizing emitter coupled logic (ECL).

Abstract: A circuit arrangement for combining a temperature compensating signal from a temperature compensator with a modulation signal to provide a combined signal for driving one or more crystal oscillators independently. The combining is carried out in such a manner that there is a constant predetermined ratio between the magnitudes of the temperature compensating and modulating signals. A potentiometer level controls the combined signal to each oscillator independently without changing the predetermined ratio. Thus, the effect of circuit element tolerances on temperature compensation is automatically corrected for while the central oscillation frequency in the absence of modulation is substantially unaffected.

Abstract: A self-oscillating vibrator exciting circuit utilizing a drive transistor that operates in a switching mode. The ON-period of the transistor is determined by base/emitter inductance and capacitance and base/collector capacitance, while the OFF-period of the transistor is determined by collector/emitter inductance and capacitance. The vibrator is connected between transistor collector and emitter, and the ON-period frequency of the transistor is set in the neighborhood of the resonance frequency of the vibrator so that the vibrator exciting circuit oscillates generally at the resonance frequency of the vibrator.

Abstract: A circuit is disclosed for driving a piezo ceramic device as used in smoke alarms or other audio warning devices. The circuit detects the resonant frequency of the piezo horn and provides an alternating current at the resonant frequency of the horn for maximum sound output. The circuit has a self starting resonant oscillation characteristic. Two pairs of switches act in concert to alternatingly connect each side of the piezo horn to the supply voltage and ground, causing the maximum voltage swing across the piezo horn to be effectively twice the available power supply voltage.

Abstract: To extend the variation range of a controlled frequency oscillator comprising a piezoelectric element, a lithium tantalate or lithium niobate element is used in parallel with which there is connected a linearization circuit comprising an inductance in series with a parallel circuit comprising a resistor and a capacitor.

Abstract: A highly stable voltage variable crystal controlled oscillator adapted for stand-alone use or for use with an atomic clock for further stabilizing the oscillator. A novel Colpitts crystal oscillator configuration is employed and utilizes an FET amplifier and bipolar emitter follower configured for power gain without phase shift in the feedback circuit. The oscillator output signal is derived through the crystal which then acts as its own low pass filter to improve the purity of the output signal. A novel buffer/amplifier circuit including a grounded gate FET amplifier and coupling transformer assure frequency stability despite wide ranging load impedance variations. A resilient thermal foam material is used to enclose the temperature and shock sensitive components of the oscillator to provide further frequency stability and rugged construction.

Abstract: An active method and apparatus for suppressing or cancelling the effects of vibration on quartz crystal controlled oscillators by generating an electrical signal which is a replica of the vibration acting on the crystal resonator, which signal is thereafter properly phased and applied directly to the crystal electrodes which thereby operates to substantially eliminate unwanted vibration-induced sidebands in the signal output of the oscillator.

Abstract: A single Colpitts-type oscillator has a plurality (here, three) of optional inputs, each having a separate oscillating circuit individually associated therewith. By suitably applying a potential to a selected one of the oscillating circuits, the oscillator may be made to produce one of a plurality of predetermined carrier wave frequencies. The inventive circuit configuration eliminates large volume components such as coupling capacitors and enables hybrid IC construction, which miniaturizes the circuit. The circuit is particularly useful in walkie-talkie FM transceivers.

Abstract: An improved oscillator circuit, adapted especially for use in generating multi-frequency wave patterns occurring within the ultrasonic range, incorporates a transistor base drive network in which an alternate discharge path is used for coupling capacitors already known in circuits of this type. Power losses occurring in the transistors are lessened by employing transistors having reverse base-emitter breakdown voltage ratings that are higher than those conventionally employed. Use of the substituted transistors becomes possible by substituting the mentioned alternate discharge path, to compensate for the lower average discharge current that is known to pass through the base-emitter circuits of the transistors by reason of their higher reverse base-emitter breakdown voltages. The improved circuit in this way reduces power loss and its consequent temperature rise in the transistors and in their base and emitter resistors to increase output power to the accompanying reduction of transistor losses.