Abstract: A focal plane scanning device arranged to move a mirror in an optical scanning apparatus, such as an infrared scanner, including a mirror, that is connected to a support by a central flexure member. An additional pair of flexure members are provided, each of which are attached at one end to piezoceramic drive elements and at their second ends to an adjustment bracket that bears against the rear side of the mirror. The piezoceramic drive elements are attached at their second ends to the support. When the piezoceramic members are energized, a balanced movement of the mirror about the first flexure member results.

Abstract: A pressure sensing device for a body movable in a fluid in a direction transverse to the longitudinal axis of the body. A chamber is provided within the body and a plurality of bores extend radially from the chamber to outer ends opening to ambient fluid so that, as the body moves, any pressure differential between the outer end and inner end causes fluid flow in the bore. Each bore is a flow restricting device such as a valve or fluidic diode, and operable to restrict outward flow from the inner end to the outward end more than inward flow thus causing the pressure in the chamber to be higher than the average pressure at the outer ends. A fluid pressure measuring device is provided in the chamber.

Abstract: The method of self repair of large scale integrated circuit modules (LSI or VLSI) in which a series of systolic processing elements (SPE's) arranged in rows (V and H) normal to each other, have sequential paths between elements biased so that normally the data being processed follows the vertical and horizontal rows to maintain a selected topography including the steps of establishing the functionality of each SPE, bypassing any unfunctional SPE by directing the data path of any row to a rear SPE in the nest row, and directing the data path from the said near SPE back to the original row to maintain the original topography.

Abstract: A microwave antenna formed with a conductive patch supported over and facing a ground plate beneath a support sheet overlapping the ground plate and spaced therefrom. An electrical lead to the patch is passed up through the ground plate to a hole through the patch and support sheet through which a solder joint is formed.

Abstract: A compound ultrasonic scan of an object is effected with a pair of transducers mounted adjacent to the object but spaced apart from each other. Each transducer is operated as a "wobbler" transducer. That is, the transducer transmits pulses of ultrasonic energy into the object and receives echoes from acoustic discontinuities in the object while the transducer is oscillated mechanically, through a predetermined angle, about an axis which passes through the transducer.

Abstract: A method for protecting synthetic and natural fibres against phototendering. The method comprises treating the fibres with a substituted benzotriazolesulfonate of the following formula: ##STR1## wherein (I) R.sub.1 is hydrogen or halogen, R.sub.2 is hydrogen or alkyl, R.sub.3 is hydrogen or hydroxy, R.sub.4 is --SO.sub.3 X where X is hydrogen or an alkali metal, and R.sub.5 is hydrogen, with the proviso that R.sub.2 is not methyl when R.sub.1 and R.sub.3 are hydrogen; or(II) R.sub.1, R.sub.3 and R.sub.4 are hydrogen, R.sub.2 is --SO.sub.3 X where X is hydrogen or an alkali metal, and R.sub.5 is --OR.sub.6 where R.sub.6 is hydrogen or alkyl; or(III) R.sub.1 is hydrogen or halogen, R.sub.2 is --SO.sub.3 X where X is hydrogen or an alkali metal, R.sub.3 and R.sub.5 are hydrogen, and R.sub.4 is hydrogen, alkyl or benzyl; or(IV) R.sub.1 is --SO.sub.3 X where X is hydrogen or an alkali metal, R.sub.2 is alkyl, R.sub.3 and R.sub.5 are hydrogen, and R.sub.4 is hydrogen or alkyl;under acidic conditions.

Abstract: A circularly polarized microstrip antenna for microwaves has a two layer substrate with a first layer of dielectric material spaced above the ground plate by an air gap comprising the second layer of the substrate, so arranged that the effective dielectric constant of the substrate in the range of 1.25 to 1.4 (for an infinite ground plane) and 1.25 to 1.6 (for a finite ground plate).The preferred values of the effective dielectric constant are respectively 1.3 and 1.5 for the infinite and finite ground plane forms of the antenna.

Abstract: A lossy transmission line in which the effective length of the line is reduced by providing resistive ferrite beads spaced along the line to provide constant power loss per unit length. Inductance ferrite beads may be included equally spaced along the line. Resistive beads are located with increasing frequency per unit length from the beginning of the line until a maximum bead density per unit length is achieved. The lossy line is suitable as a terminating unit for a portable travelling wave antenna and in other situations where size reduction is desirable.

Abstract: A programmable electronic delay fuse for initiating a firing after a programmed and accurate delay time has been chosen, comprising a fire control unit (FCU), a programming unit (PU) to program and test the fire control unit (FCU), and optical coupling interface means (1) on each unit to electrically interconnect firing and status means (3) on the fire control unit (FCU) with command and test means on the programming unit.

Abstract: The data synchronizer overcomes problems with mismatched recording and analyzing equipment and can be used for multiple channel recording. By preliminary analysis a reference point is located on the record signal and used to trigger the data processor. Each channel of the recorder is then played into the data processor using the data synchronizer to provide a triggering signal for the data processor. Each channel is thus able to be analyzed from the same time reference. The data synchronizer decodes the recorded three level digital signal during playback and provides an output synchronizing pulse to externally trigger the computer system. This pulse occurs at the same instant relative to the data recorded each time the tape is played back, regardless of the playback speed.

Abstract: A squelch circuit in which a phase locked loop (PLL) (5) having a voltage controlled oscillator (VCO) (7) and a phase comparator (10) is used to detect the number of zero crossings, these being low for a speech signal and high for noise. The error voltage produced in the phase locked loop (5) is fed through a network (12) which ensures that the matching of the input signal to the oscillator is faster when the input frequency drops than when the input frequency rises. The input signal is clipped to enhance the frequency spectra of speech by using a limiting amplifier. The muting gate (2) output is derived from the VCO (7) control voltage of the PLL (5) to mute the output of the receiver when the VCO (7) output frequency is higher than a pre-set frequency for more than a pre-set time.

Abstract: A marine gyro compass output is corrected to take account of accelerations cting upon the ship in which it is installed by calculating about once per second a correction capable of expression by differential equations which are solved by numerical methods by taking small but finite time increments to linearise the equations with regard to time, the current calculated correction factor being applied to correct the gyro compass output many times per second. The corrections can take into account (a) ship north-south acceleration, (b) change in Coriolis acceleration, (c) earth rotation rate and (d) azimuth error for east-west speed. Furthermore, account can be taken of the constant characteristics of the particular gyro compass to be corrected in terms of its tilt limit, its period of damped oscillation, its damping and the characteristics of the compass electrolytic level which determines tilt.

Abstract: A solar reaction system which produces hydrogen by reduction of hydronium ions using methylviologen or a related compound as an electron-transfer agent and a platinum electron-transfer catalyst, wherein the catalyst is modified with a water-soluble divalent sulphur compound, or a sulphur compound in which the sulphur is reducible to the divalent state, in an amount sufficient to inhibit hydrogenation side-reactions during the solar reduction process but not sufficient to significantly suppress the reduction of hydronium ion to hydrogen by the electron-transfer agent.

Abstract: A conducting composition suitable for use in a firing cap is disclosed. The conducting composition comprises normal lead styphnate which has a mean particle size not less than 55 microns, in admixture with carbon black which has a mean aggregate size between 5 microns and about 15 microns. The conducting composition has less sensitivity than known conducting compositions and therefore when used in a conducting cap renders the cap less likely to unintential ignition by induced e.m.f. such as from radio transmitters or the like.

Abstract: A method for measuring the purity of water in which the water is passed through an insulated pipe (1) in a cell spaced between electrodes (2-3) for measuring the tribo-electric electromotive force (e) generated by the flow, and wherein the resistivity of the water is calculated from the measured electromotive force.

Abstract: Thrust augmentation apparatus for a propulsive gas jet 11 including: an outer augmentor housing 15 and an inner augmentor housing 21 arranged coaxially with the jet 11. A minor air flow 25 is drawn into the inner passage 24 by an ejector effect, that flow 25 driving turbine vanes 28 projecting inwardly but terminating short of the jet 11. The vanes 28 transmit drive to fan blades 13 in the outer housing 15 to promote a thrust augmenting air flow 14. As an alternative to turbine vanes 28, gas scoops 32 may be used to develop the energy for creating the air flow 14.

Abstract: A flight test aid comprising means to measure force that is applied by a pilot to the controls (7) of an aircraft to adjust the control surfaces while manoeuvering the aircraft which utilizes a plurality of sensors (5-6) supported in the interface between the control member (7) and the part of the pilot (1) operating the control and means (9) to record the force from the sensors (5-6) preferably through differencingmeans (21) to cancel pressure applied equally to the sensors (5-6). A typical example is a glove (1) with finger and palm sensors (5-6) connected to indicator means (9) preferably through a differencer (21).

Abstract: A missile for airborne and seaborne use in which directional control about a flight axis comprises a nose (2) deflectable angularly in relation to the flight axis of the body (1) of the missile to form steering means by changing the fluid flow involve over the body (1) and means (4,5) between the nose (2) and the body (1) to effect angular deflection about a universal pivoting point (3) between the nose (2) and the body (1).