Abstract: A test signal generator for pseudo-simulated non-intelligible speech. The generator comprises first and second ROM's controlled by first and second address counters driven by a single clock. The first ROM generates digital samples which when decoded produce a random signal having a gaussian amplitude distribution. The second ROM also generates digital samples which when decoded produce a modulating signal having a power spectrum substantially equal to that of the modulation envelope of speech and a wave shape that results in a gamma amplitude distribution of a gaussian amplitude distributed signal. Each cycle of the modulating signal has an identical wave shape but a randomly varying wave period.

Abstract: Dual monolithic one-shot multivibrators one of which is connected to receive the FM signal and convert it to pulses and the other of which has a reference oscillator connected thereto for conversion to pulses, the output pulses of both multivibrators being low pass filtered with the filtered signals being combined for differential cancellation to provide a detected signal substantially independent of temperature.

Abstract: An adjustable frequency synthesizer primarily for use in an atomic frequency standard of the type used for stabilizing a frequency source by locking it to the hyperfine transition resonance of an atomic frequency resonator. The synthesizer is programmable by an externally applied code to provide the proper frequency, electromagnetic resonance field to the atomic frequency resonator. The synthesizer also provides a phase locked frequency modulating signal to produce the resonance deviation signal in the resonator. The broad range and fine frequency increments of the synthesizer permit accommodation of a wide range of resonance frequencies in the atomic frequency resonator to obviate resonator gas pressure and magnetic field variations which would otherwise decrease the production yield of such resonators.

Abstract: A device using a dielectric resonator with a very low temperature coefficient in a very high frequency transistor oscillator (3 to 10 GHz) so as to benefit both from the very high power available and the maximum frequency stabilization due to the resonator. In the case of a FET, the gate is connected to one end of a line coupled to a dielectric resonator at a point along the line situated at a quarter wavelength from the other end of the line, which in turn is connected through a discrete resistor to a half wavelength open circuit line. Thus, the oscillation is damped when the frequency varies from the resonant frequency of the resonator.

Abstract: A sampling PLL circuit features a frequency sweep caused by an offset voltage applied to an integrator to avoid false lock ups. At one end of the frequency range the polarity of the offset signal can be reversed. The error voltage can be sampled during a television vertical or horizontal blanking period. Once proper lock up is achieved, the offset signal can be removed.

Abstract: An improved presettable integrator circuit is disposed in a fast frequency changing phase lock loop for presetting the voltage-controlled oscillator thereof as governed by a preset signal and a pulsed signal generated by a frequency controller. One input of the integrator circuit is coupled to the preset signal, another input is coupled to an integrator control signal, and the output is coupled to the voltage-controlled oscillator for use as a tuning signal thereof. A switch is included in the integrator circuit and is governed in a first state by the pulsed signal to cause the integrator circuit to respond rapidly to an applied preset signal to preset the output signal thereof. In a second state, the switch renders the integrator circuit responsive to an integrator control signal which is selected by a phase lock condition of the loop from either a reference signal or a filtered phase error signal, being coupled to the other input of the integrator circuit.

Abstract: A lamp assembly primarily for a rubidium frequency standard and having an improved lamp housing configuration including a cast metal housing which acts as an RF shield for the lamp ignition helical coil resonator. The lamp is heated by both a conventional bipolar heater transistor and a heater blanket made of Nichrome etched Inconel encased in a Kapton impregnated fiberglass laminate material, to reduce warm-up time and more reliably distribute the heating function.

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.

Abstract: A circuit used in a traffic control apparatus for detecting changes in the frequency of an oscillator which has an inductive loop-sensor as a resonating element. The circuit comprises a phase-locked loop oscillator with restricted tuning range and a high impedance amplifier followed by threshold detectors adjusted to sense the entry and exit of a vehicle over the area covered by the loop-sensor. The high-resolution of the circuit overcomes long-term drift problems inherent to loop-sensor detectors with analog circuitry.

Abstract: A low cost arrangement for a millimeter wave solid state diode oscillator, hich obviates precise machining and uses a dielectric transmission line associated with a resonant cavity. Coupling and impedance matching are greatly facilitated by a conductive stripe structure on the end of the dielectric transmission line, extending into the resonant cavity of the solid state oscillator. Fine tuning is provided by a mechanical slide screw. Two layers of shielding surrounding the resonant cavity are provided by a convenient package suitable for various applications of the millimeter wave oscillator wherein leakage radiation is not permitted.

Abstract: A modulated carrier signal, the amplitude variations of which are smaller than the amplitude of the unmodulated carrier, is not very suitable for transmission over radio links because the required use of non-linear components, such as class-C amplifiers, result in an unwanted widening of the transmitted spectrum. According to the invention an arrangement for amplifying such a signal comprises two oscillators (16, 17) the desired relative phase of which is adjusted in a loop including a control circuit 22. On combining the oscillator signals v'.sub.k and v'.sub.g, there is produced a resulting signal r which is a replica of the input signal v having the amplitude variations. As the oscillators 16 and 17 produce signals having a constant amplitude, these signals can be easily amplified, for example by class-C amplifiers.

Abstract: A circuit for linearizing the oscillator sweep output frequency signal of a oltage controlled oscillator is disclosed. The voltage controlled oscillator is driven by the output of an op amp, which amplifies and filters the output of a D/A converter. The D/A converter responds to preselected 8-bit words, stored in an EPROM, so as to produce a desired output frequency at each memory address. The addresses, in turn, are provided by a combination of gates, counters, input signals and a clock.

Abstract: A proximity sensor includes a housing having one compartment which houses the components of an oscillator control circuit and another compartment which houses a sensing head including a ferrite core and oscillator coil assembly. An end cap closes the open end of the sensing head compartment. A fluid passage is provided in the end cap which permits fluid to flow around the oscillator coil assembly. A relatively thick seal assembly is interposed between the one compartment and the oscillator coil assembly to prevent the passage of fluid into the one compartment.