Abstract: A fast risetime, high voltage, high impedance voltage probe utilizes a parallel R-C divider with damping and compensation circuitry to allow measurement of voltage from DC to picosecond pulses. A unique feature of this probe is its construction. The performance of this device is made possible by utilizing microwave chip components on a planar circuit used as the center conductor of a coaxial transmission line.

Abstract: An improvement in the technique of correcting the angles of cut of quartz resonator plates is disclosed. Photolytic etching the crystal blanks comprises the preferred method. Flat-pack or pill-box type holders include masking members which mask the appropriate portion of the blank. Teflon and Kalrez comprise preferred materials for fabricating the masking elements since such materials are resistant to the etching material utilized. Mesas are formed during etching and the blanks are thereafter lapped to provide the desired angle of cut. When desirable, the masking element is withdrawn at a uniform rate during etching so that the angle is corrected without the need for lapping.

Abstract: Millimeter wave circulators are disclosed for use with millimeter wavelen dielectric waveguides. The structure comprises a prism of magnetized ferrimagnetic material with the waveguide ends bonded to the lateral faces of the prism. The waveguide ends and the lateral faces are congruent rectangles. The prisms may have triangular bases in which case a Y-junction circulator results, or square bases with waveguide ends attached to three out of four of the lateral faces thereof, whereby a T-junction circulator results.

Abstract: A nozzle beam source for use in the vapor deposition of electrode materials such as gold, during the fabrication of precision quartz-crystal resonators, or the like. The nozzle beam source includes a graphite crucible and source tube, a tungsten wick within the source tube, and graphite-to-graphite mechanical seals.

Abstract: The thermal properties of a crystal resonator are rapidly and inexpensively measured by first immersing the resonator into an ice water bath at 0.degree. C. and monitoring the frequency of the resonator until the frequency of the resonator is no longer changing; then rapidly immersing the resonator into a boiling water bath at 100.degree. C. and monitoring the frequency versus time characteristic of the resonator at least until the frequency of the resonator is no longer changing; repeating the above cycle, and determining the thermal properties of the crystal resonator from the frequency versus time characteristic.

Abstract: An apparatus and method for precisely measuring the angles of cut of single nd doubly rotated cuts of quartz crystal blanks on a high volume production basis.

Abstract: Apparatus and method are described for fabricating a long life cold cathode lectron beam semiconductor device (EBS). Fabrication is given of a vacuum tube structure capable of sustaining sufficiently high vacuum over extended time to prevent poisoning of the cold cathode and steps are give for growth of a plural tip cold cathode structure.

Abstract: Disclosed is a majority carrier rectifying barrier semiconductor device housing a planar doped barrier. The device is fabricated in GaAs by an epitaxial growth process which results in an n.sup.+ -i-p.sup.+ -i-n.sup.+ semiconductor structure wherein an extremely narrow p.sup.+ planar doped region is positioned in adjoining regions of nominally undoped (intrinsic) semiconductive material. The narrow widths of the undoped regions and the high densities of the ionized impurities within the space charge region results in rectangular and triangular electric fields and potential barriers, respectively. Independent and continuous control of the barrier height and the asymmetry of the current vs. voltage characteristic is provided through variation of the acceptor charge density and the undoped region widths. Additionally, the capacitance of the device is substantially constant with respect to bias voltage.

Abstract: An acceleration resistant crystal resonator is made from a single quartz te that is optically twinned into a left-handed (LH) quartz portion and a right-handed (RH) quartz portion. According to the method, the optically twinned single quartz plate is formed into a resonator plate wherein the effective thickness of the (LH) portion is substantially the same as the effective thickness of the (RH) portion. The resonator plate is then mounted and bonded to the support structure of a crystal resonator enclosure. A pair of electrodes is then deposited onto the (LH) portion and a pair of electrodes deposited onto the (RH) portion. The thickness of the two pairs of electrodes is then adjusted so that the resonant frequency of the resonator on the (LH) portion is substantially the same as the resonant frequency of the resonator on the (RH) portion. The pairs of electrodes are then interconnected to each other and to an oscillator circuit so that in-phase vibration of the two portions is assured.

Abstract: A crystal resonator features two crystals mounted such that the acceleration sensitivity vector of one crystal is in an antiparallel relationship to the acceleration sensitivity vector of the other crystal. The composite resonator eliminates acceleration-induced frequency shifts for acceleration in all directions.

Abstract: A variety of technologies have been applied in the development of a bonded rid cathode. Erosion lithography is used for making the fine-detail grid structure, combining air erosion and lithographic techniques. To obtain openings of the order of 0.001 inch (one mil) or smaller, a nozzle with a high aspect ratio exit opening is used, and the cathode grid structure is scanned. A photo resist in which the grid pattern is developed is used over the molybdenum or tungsten grid film. The metal film is removed from the grid openings by chemical etching. The photo resist over the metal grid is used as a composite mask for removing the BN insulation in the openings by erosion with Al.sub.2 O.sub.3 powder from the special nozzle on the air blast gun.

Abstract: An accurate and constantly updated attitude instrument is provided for aiaft. The pitch and roll angles are calculated from two sets of velocity measurements, one set being derived from signals received from orbiting navigational satellites and the other set from on-board equipment which determines the aircraft's axial velocities. The on-board equipment may be a Doppler ground-speed sensor or an inertial system using accelerometers, the outputs of which are integrated to derive the axial velocities.

Abstract: Disclosed is an in-band, non-sampling, real time VHF radio relay or signal epeater for use in two-way, multi-hop remote sensor data links. Each signal repeater comprises a transceiver which includes interference cancellation circuits for preventing the high level signal produced by the radio repeater's transmitter section from desensitizing the low noise RF amplifier circuitry incorporated in the front end of the radio repeater's receiver section. Such apparatus is utilized to implement a remote sensor data collection network consisting of a plurality of subject radio repeaters and several sensors normally arranged in groups. The data which flows over the relay network can either originate at the sensors and flow to a read out station or it may originate at the read out station and flow to the sensors. Sensor originated information may be either digital or analog, or both, while read-out station originated information is digital only. The relay operates with either analog or digitally-modulated signals.

Abstract: The invention is an improved manufacturing technique for producing a certain class of Surface Acoustic Wave (SAW) devices, namely those having input and output transducers in close proximity. A much higher manufacturing yield results from eliminating the cutting of a slot in the substrate between input and output transducers as formerly done. This frequently destructive step is replaced by ion-milling of a deep groove between the ports and backfilling with a metal of proper configuration to provide electromagnetic shielding. The technique produces a new device that is at least equal to the prior art in rejection of unwanted couplings between input and output.

Abstract: An interlock arrangement in which each service request path comprises two inverter gates between an input and an output with a junction between the gates. Cross-coupling circuits are coupled from each junction to every other junction in each direction, each comprising an inverting gate in series with a diode. The diodes are normally reverse biased. A first to arrive request signal is forwarded to its output, and a later signal at any other input causes one diode to conduct and clamp the junction at its output, so that the signal is blocked from reaching the output until the first request signal returns to the inactive state.

Abstract: An accurate and constantly updated heading reference is provided for movee vehicles, particularly aircraft. The heading is calculated from four velocity measurements, two of which are obtained from signals received from orbiting satellites, and two from on-board equipment which determines the vehicle's along-track and cross-track velocities. The on-board equipment may be a Doppler ground-speed sensor or an inertial velocity sensor using accelerometers, the outputs of which are integrated.

Abstract: An electronic detection system for detecting intruders employs a transmisn line as a sensing element. In one embodiment the transmission line is a modified surface-wave transmission line, for example, a Goubau line which is positioned about the perimeter of the area to be protected. An intruder in the field of the line causes an RF reflection back toward the source, which reflection may be detected by Doppler range-gating techniques. In other embodiments of the invention, the transmission line is an insulated, twisted wire pair or a deformable transmission line. In some instances, the transmission line may be replaced with an active or passive pressure line.

Abstract: An electronic detection system for detecting intruders employs a transmisn line as a sensing element. In one embodiment the transmission line is a modified surface-wave transmission line, for example, a Goubau line, which is positioned about the perimeter of the area to be protected. An intruder in the field of the line causes an RF reflection back toward the source, which reflection may be detected by Doppler range-gating techniques. In other embodiments of the invention the transmission line is an insulated, twisted wire pair or a deformable transmission line. In some instances, the transmission line may be replaced with an active or passive pressure line.

Abstract: A high power, broadband, active transmitting antenna for operation in the frequency range below 1 GHz which is in the order of 0.15 wavelength in electrical size. The relatively small antenna is coupled across an electron bombarded semiconductor device in the form of a diode which is penetrated by high energy electrons from an electron gun modulated with the RF signal to be transmitted.

Abstract: A harmonic frequency generator responsive to an input signal of frequency f hich changes slowly in both frequency and amplitude and characterized in that (1) the output signal (harmonic) amplitude remains proportional to the input signal amplitude and (2) the output frequency nf of the output signal consists soley of one integral (n>1) multiple of the input signal frequency.