Abstract: End terminations for multilayer ceramic dielectric capacitors, particularly but not exclusively metal-impregnated capacitors, are provided by bonding a coarse ceramic powder, which is lightly coated with silver, to the capacitor ceramic by means of a glass frit in order to produce a porous pseudo end termination containing insufficient silver to provide a good contact to the capacitor electrodes. The exposed silver in the pseudo end termination is then provided with a silver sulphide layer and subsequently the pseudo end termination is impregnated with lead. The end termination thus formed is comprised substantially of lead, which is held in place by the silver sulphide layer, that is wetted by the lead, on the bonded ceramic powder, and thus low cost and readily solderable.

Abstract: The rate at which glass optical fiber can satisfactorily be coated with a primary plastics coating by a liquid application method is enhanced by causing the fiber to enter the liquid contained in a coating vessel via a suction tube in which a partial vacuum is maintained by an air induction device. Optionally a funnel is used to deflect the exhaust away from the incoming uncoated fiber.

Abstract: The digital supervisory circuit comprises an amplitude comparator and EXCLUSIVE-OR gate to provide an output signal indicating the difference in time an input signal is above and below a predetermined reference potential. This output signal is integrated in an up-down binary counter and also is coupled to a first logic circuit under control of the counter which provides a ring present supervisory signal when a first threshold is exceeded and a second logic circuit under control of the counter which provides a switch hook detection supervisory signal when a second threshold is exceeded. A hit-timing circuit is provided coupled to the counter and the first and second logic circuits to prevent response of the counter and second logic circuit to line transients.

Abstract: An arrangement for storing a coil of optical fiber prior to and during an inner peel deployment of the optical fiber from the coil comprises an outer aluminum casing, a body of solid foam material in the interior of the casing, and a barrier sheet in the interface, between the foam body and the coil of optical fiber. The foam body is formed in situ in a confining space outwardly and axially delimited by the casing and inwardly delimited by the barrier sheet and by two end lids, by introducing the material of the body into the enclosed space through openings in the casing and letting the material foam and cure in the spacing. During the formation of the body, the coil of optical fiber is supported on a mandrel which is, in turn coaxially supported on the end lids. After the foamed material has solidified, the end lids and the mandrel can be removed and the arrangement is now ready for inner peel deployment of the optical fiber therefrom.

Abstract: The broadband injection locked oscillator system comprises a first voltage controlled oscillator having a signal output for a first signal controlled to have a first frequency in a first relatively broad frequency range, and a second voltage controlled oscillator having a signal output for a second signal controlled to have a second frequency in a second relatively broad frequency band. The output of the second oscillator is coupled to a signal input of the first oscillator to injection lock the first oscillator to the second oscillator. The second frequency is harmonically related to the first frequency when the injection lock occurs.

Abstract: An assembly for bidirectional signal transmission over a single fiber is disclosed together with its method of manufacture. A hot coating of dichroic material is applied to a surface of a glass substrate. The substrate is processed into dichroic wafers having larger dimensions than the cross section of the fiber with which it is employed. The dichroic wafer is positioned over the end face of a polished fiber beamsplitter and secured thereto by a thin layer of optical grade epoxy. A second polished fiber beamsplitter may than be secured in a similar manner to the opposite side of the wafer. The coated wafer forms an acute angle of about 25.degree. with a plane perpendicular to the axis of each beamsplitter half. A bidirectional coupler is thereby formed.

Abstract: An operational amplifier is disclosed which is capable of handling input voltages in excess of 200 volts, comprising at least in the input stage thereof a plurality of low voltage transistors including at least a pair of low voltage lateral PNP transistors each having two collectors. These lateral PNP transistors act as level shifters for the amplifier and also a bias arrangement for the input stage. A single high voltage lateral PNP is in the signal path providing the lowest pole in the transfer function and to compensate for low to medium loop gains.

Abstract: A binary data transmission system uses a code consisting of n-bit code words of a quasi-cyclic code with k information bits and n-k check bits. An encoder and a decoder with an error-detection and -correction facility are provided which use a quasi-cyclic code that has a high error-correcting capacity and requires little storage space.

Abstract: There is disclosed a night vision imaging system for mounting on a helmet. The helmet contains a visor having a slot into which is inserted a helmet mount assembly which can be vertically adjusted within the slot by means of a control mechanism including a rotatable knob. The mount assembly is an arcuate planar member conforming to the surface of the helmet and contains two "U" shaped receptacles for receiving two pivots located on a central fork support frame. The fork frame has two adjacent tines which are secured within two slots contained in a gear box. Coupled to the gear box are right and left carriage assemblies which interface with the gear box by means of a first threaded shaft to afford eye relief adjustment and a second rod assembly to afford tilt adjustment. Each carriage assembly is symmetrically positioned on the right and left sides of the gear box assembly and are coupled to a first and a second unity power image intensifier telescope housing containing an image intensifier tube.

Abstract: In an assembly of a piezoelectric crystal and an IC on a substrate, additional capacitors, such as load capacitors of a crystal oscillator, are designed as blocks for mounting the crystal on the substrate at its vibration nodes.

Abstract: The asynchronous integrated voice and data communication system includes a continuously variable slope delta encoder and a continuously variable slope delta decoder to convert voice signals to coded signals and vice versa. A packetizer and a depacketizer are employed with each data and voice user to enable each of the plurality of data and voice users to have random access to a fiber optic transmission medium enabling each of the plurality of data and voice users to receive transmissions from all others of the plurality of users. A microcomputer is coupled to each of the voice and data users and the associated packetizer and depacketizer to enable any one of the plurality of data and voice users to establish communication with any other selected one of the plurality of data and voice users.

Abstract: Conductive and porous end terminations for metal-impregnated multilayer ceramic dielectric capacitors are provided by firing a silver, or silver alloy, and glass frit onto respective end regions of a sintered capacitor stack. The exposed silver of the fired terminations is provided with a silver sulphide layer, the latter being a good electrical conductor and acting as a barrier between the silver and the impregnation metal, for example lead, during a subsequent impregnation step, whereby to prevent leaching of the silver. The termination is readily solderable by virtue of the silver sulphide layer being wetted by the lead during the impregnation step and resulting in a lead coating in the termination.

Abstract: A plastic fiber cable has a flame retardant sheath which contains between 10-40% by weight of an inert filler, preferably titanium dioxide, which provides the sheath with thixotropic non-drip properties so that as well as possessing non-flammability properties the sheath when molten will also not drip and thus will not expose more flammable materials, such as the strands, inside the sheath.

Abstract: Airborne Tacan equipment includes a receiver to receive Tacan signals and to provide an output signal having modulation components containing bearing information. The receiver includes a logarithmic amplifier to preserve the amplitude modulation of the modulation components and to enable operation on input signals having large amplitude variations. An arrangement is coupled to the receiver to at least partially compensate for the non-linearity of the logarithmic amplifier prior to extraction of the bearing information.

Abstract: Reactor apparatus for use with a gaseous plasma includes a grounded electrode in contact with the plasma. The electrode includes one or more bores in which plasma jets form.

Abstract: There is disclosed a method and apparatus for providing call clearance in a packet-switched data communications system. The apparatus disclosed detects the request of an originating terminal to end a call and delays the request for a predetermined calculated time period. The period is determined according to the length of the message being transmitted, the number and type of transmission links being traversed and the speed of transmission of the sending and receiving terminals. At the termination of this period the apparatus issues a normal clear request which then disconnects the connection while assuring that any data which may have been delayed reaches the destination terminal.

Abstract: A tubular formation of particulate optical material is formed by a layer slurry deposition process which involves spraying layer after layer of slurry containing particles of the optical material onto a rotating rod-shaped bait. The composition of the slurry and particularly the index of refraction of the optical material may be varied from one layer to another or from one group of layers to another to obtain a graded or stepped refraction index profile in the formation, in an optical preform formed therefrom, and ultimately in the fiber drawn from the optical preform. The particles of the slurry are suspended in a liquid vehicle which evaporates in the spray stream or shortly after deposition, and are coated with an organic binder which holds them together in the layer and in the formation, so that the formation is self-supporting. Then, the organic binder is removed and the formation is sintered, followed by a collapse of the sintered tubular formation into the optical preform in the form of a solid rod.

Abstract: In order to provide a high power heat source having a very clean and invariable heat flux, a ring plasma is induced in a heating zone of a plasma torch including a plurality of coaxial tubular elements and the optical fiber is drawn through a channel passing axially through the center of the plasma torch and of the ring-shaped plasma. In this manner the preform from which the fiber is drawn can be placed in close proximity to the induced plasma without exposure to non-symmetrical temperature variations. Cooling gas passes through the heating zone either in an annular stream surrounding the plasma or in an annular stream passing through the center of the plasma around the preform and the fiber being drawn, or both. The heating zone is protected from environmental disturbances by an extension of the outer tubular element of the plasma torch which surrounds the heating zone.