Abstract: A terminal station for communication with one or more similar remote stations via mains wiring includes a piezo-electric coupler (22) whereby carrier signals are transmitted to and received from the line (24). The coupler is driven by an oscillator (21) modulated in correspondence with an input signal and tuned to the resonant frequency of the coupler.

Abstract: A co-ordinate matrix addressing system is used to address a liquid crystal display cell containing a positive dielectric anisotropy smectic material. For this purpose one or more direct voltage pulses are applied across selected elemental volumes of the display to convert them from a focal-conic scattering state to a homeotropically aligned state. Prior to this all elements are electrically driven into the turbulent scattering state which relaxes into the focal-conic scattering state upon removal of the driving field. The driving field may also take the form of direct voltage pulses. Unselected elemental volumes may be refreshed to substantially their original level of focal-conic scattering by means of a suitable blanking potential applied to both selected and unselected elemental volumes which nevertheless leaves previously restored elemental volumes in the homeotropically aligned state.

Abstract: A multichannel duplex radio system for cordless telephone in which digital information is sent between the two ends. The data is divided into blocks which are transmitted in a fraction of the original block length. The other time slots are used for the duplex return path and for other similar equipment operating nearby. A direct conversion radio receiver is used in which the local oscillator signal is modulated for transmission.

Abstract: A radio receiver for FM signals having a demodulation system to produce an approximation to an analog output by either measuring the time intervals between successive zero crossings in the I.F. (FIG. 1, FIG. 2B) or by filtering pulses produced at each zero crossing of the I.F. (FIG. 1, FIG. 2A). The demodulator includes two signal pathways in quadrature phase relation, the second signal either lagging or leading the first signal in dependence on whether the received signal frequency is above or below a local oscillator frequency. The modulation frequency can carry analog information separate and apart from the on-off (digital) information.

Abstract: A rod of silica 14 is inserted into a substrate tube 10 whose bore is lined with a layer 11 of material having a refractive index less than that of silica. This layer 11 is itself covered with a layer 12 of silica. The assembly of the rod and tube is drawn into fibre, or its components are fused together to form a solid cross-section optical fibre preform.

Abstract: As is well known, a virtually flicker-free picture is obtained by using a sufficiently high picture-reproducing frequency and doing without interlaced scanning. This is achieved with a suitable standard converter in which the picture is temporarily stored in digital form. By suitable multiplexing, the digital frame store (221, 222, 223) can also be used for the conversion of the text and graphics page. Multiplexer (26) and demultiplexer (27) are switched by a blanking signal (Blank, Blank') which is buffered in the frame store together with the associated picture section.

Abstract: This invention relates to continuous manufacturing of insulated wire and conductor, and in particular to heating cables having "cold ends". A process is described by which predetermined lengths of resistance conductor (4) and of cold end conductor (9) are continuously and alternatively jointed together. After insulation and provision of additional protective sheats the continuous composite conductor is cut into cold end heating cables. A conductor jointing process is described.

Abstract: A tray loading apparatus includes an inclined support having a displaceable front part so that the front wall of a tray can be brought into abutment with the front end of a stack carried by the support and to be loaded in the tray after a backing plate supporting the stack front end has been removed. The stacking apparatus includes a conveyor able to apply the front portion of each envelope conveyed in a direction making an angle with the above backing plate against this backing plate and a belt arrangement operating on the front portion of each envelope to cant the rear part of the envelope into engagement with a deflector after the front portion has been applied against the backing plate.

Abstract: A method of manufacturing thin film dielectric material by directing vapors of reactants containing lead and additional metals and an oxidizing gas onto a heated substrate to form a layer of dielectric material thereon, which layer can be of a high dielectric constant (greater than 5000).

Abstract: A curtailed drive scheme for a matrix array liquid crystal display cell in which the field developed across each picture element is maintained for only a fraction of the time interval between consecutive addressings. This reduces the effects of differences in time constants across the display for addressing schemes in which the average time constant is short compared with this time interval between consecutive addressings.

Abstract: A method is disclosed which permits instant-heat cathodes for color-picture tubes to be formed in a single process step and avoids the formation of an activated barium-oxide deposit on the grid cylinder. This is achieved by alternately switching the heater current on and off with the operating voltages applied, the heater voltage and the "on" and "off" periods of the heater current being chosen so that, averaged over the "on" and "off" periods, the rated heating power and the rated power dissipation are maintained during the formation process, and that, when the temperature of the emitting material decreases during the "off" periods, no saturation of the electrode currents occurs.

Abstract: A component-insertion table is provided with a receptacle (take-up device) for the circuit carrier, a programmable adhesive dosing feeder and a programmable component dispensing unit. The receptacle containing the circuit carrier is moved coordinately below a cover of the component-insertion table to a centrally located position for the automatic application of an adhesive with the aid of the adhesive dosing feeder, as well as into a centrally located insertion position for the manual placement of the components. The adhesive-application position and the insertion position be within a window in the cover through which the individual component insertion locations on the circuit carrier are made from above in a programmed order of succession.

Abstract: A method of making a channel substrate buried heterostructure InP/(In,Ga)(As,P) laser avoids the need to use two separate stages of epitaxial growth by using a channel in a (100) surface substrate 1 extending in the [011] direction with {111}B sides. This allows the channel to be made before the growth of an (In,Ga)(As,P) blocking layer 3 which can be grown under conditions which do not require the use of a mask to prevent nucleation on the channel sides. The same technique is also applicable to the manufacture of a terraced substrate laser incorporating a blocking layer.

Abstract: A liquid crystal display device has a tandem arrangement of two cells. The rear cell is an active silicon matrix backed dyed nematic cell with 180.degree. twist cell affording the possibility of grey scale representations. The front cell is a dyed nematic cell oriented to act as a variable density polarizer to absorb the weakly absorbed plane of the rear cell. Control of this absorption is used to optimize the contrast perception in the rear cell under different ambient lighting conditions.

Abstract: At least one metallic element is incorporated into a cable during the manufacture of optical fiber cables, along with one or more elongated optical fibers. Such metallic element with its insulation is similar in diameter to an optical fiber with its sheath. The electrical resistance of the metallic element varies very little with temperature, but does vary with strain. Hence, by monitoring the resistance of the metallic element, the strain to which the fibers are subjected can also be monitored.

Abstract: A leakproof electromagnetic relay in which a pourable sealing compound is introduced into the interior of the lower housing of the relay. A recess is formed in at least one sidewall of the housing through which the sealing compound is poured. The compound distributes itself equally on the bottom of the housing and flows into the separating points or gaps of the housing by capillary action. A cover closes the recess after the compound has been poured in. The invention permits the relay to be sealed in its upright position and further processed.

Abstract: In the manufacture of display structures--including fluorescent material displays--by means of a print process, a base material (glass or plastic material), prior to the print process, is coated with an electrically conductive layer. During the print process, a strippable coating or pigmented lacquer having the shape of the structure, is deposited onto a first layer. After the print process, the non-printed electrically conductive layer is etched away and in the case of the non-fluorescent display structure, the strippable coating is peeled off the electrically conductive layer. The invention provides an improvement in the manufacture of display structures over the hitherto conventional photographic reproduction of silk-screen printing methods, and provides display structures having sharp edges to a thickness of approximately 10 .mu.m.

Abstract: The disclosed invention relates to an electro-optical device for use with a facsimile printer, telecopier, etc., designed to accommodate line-at-a-time output of picture information with the aid of an electrically controllable electro-optical substrate. In particular, there is disclosed a solution to the problem of adjusting the electro-optical elements to provide the desired rectilinear output of picture information. The electro-optically active substrate (1) is supported in a frame-like housing (17) such that it may be adjusted perpendicularly relative to a longitudinal edge (18) of the substrate (1) by means of an adjustable ledge (31) and a resilient support (33). A beam of light from a light source (37) is shaped and directed onto the substrate by means of a light-shape converter (36) which can be adjusted relative to the substrate by means of a cross slide arrangement (51, 57) having 2.degree. freedom.

Abstract: A method of synchronizing a digital radio pager receiver with incoming digital data signals. At switch-on the receiver first attains a "course" bit synch during the first quarter-word period and then a "fine" bit synch during the next half-word period. The receiver then examines incoming data bits to determine simultaneously (a) whether valid data is being received and (b) whether the incoming data contains a preamble sequence. If either determination is successful the incoming data is then examined to determine whether it contains a synchronizing word or an address word. The synchronization and address word determination is also carried out while bit synch is obtained and the valid data/preamble determination is effected.

Abstract: A system for monitoring the level of an RF signal having such a small amplitude that it must be amplified before it can be monitored. To determine the deviation of the amplifier gain from the desired value, an additional RF signal of relatively high amplitude is used and is attenuated by a predetermined amount before being applied to the amplifier. The levels of the attenuated and subsequently amplified RF signal are compared with the level of the unchanged signal. From the deviation of this ratio, the gain variation is determined.Alternatively, in lieu of gain control of the amplifier the gain variation may be mathematically offset in the digital instrumentation provided.The monitoring system is suitable for use in the so-called instrument-landing system (ILS) and in VOR and DVOR en-route navigation systems.