Abstract: Disclosed is a thin film photodetector array of resistance-variable light detectors and a method for manufacturing such an array. Electronic read-out circuitry is normally associated therewith.

Abstract: An integrated optical-to-electrical signal transducing system and apparatus therefor which, through the use of a novel combination of fiber optics and microelectronics, permits locating the optical signal detection circuits close to their associated preamplifier circuits and remote from sources of interfering signals without losing the ability to do effective optical tracking or seeking. Specific structure including a hybrid microelectronic device package modified to receive optical input signals through a fiber optics terminal incorporated therein is provided to achieve the desired results.

Abstract: Novel apparatus is provided which permits the additive combination of the peak pulse power from multiple avalanche diodes operating in the IMPATT mode without spurious signal generation and includes the use of radially disposed combinations of avalanche diodes and coaxial transmission line resonators feeding a common signal output coupler.

Abstract: A low mass inertia scanning system is used in conjunction with a servo control system to make high frequency changes in beam direction. The scanning system is placed behind a beam expansion optical system, which reduces the mass-inertia and increases its directional accuracy. When used in the reverse direction, with beam reduction, it can be used to increase the directional movement. A beam scanning system, refractive or reflective, diverts the ray direction from or toward the primary optical axis. A beam expander, a telescope in reverse, projects the beam, for instance, to a moving target. Alternately if the source-director-telescope is moving, it can keep the beam on a stationary or moving target. The beam direction or image is maintained in the same position, irrespective of source-director-telescope or target movement, by means of a sensing device and a servo system which appropriately adjusts the position of the scanning system (director) to accommodate such position change.

Abstract: A refrigerating apparatus enclosing the rivet hoppers of an automatic riveting machine. A refrigerant such as liquid nitrogen is conducted into the refrigerant coils of an insulated enclosure to maintain the temperature of the rivets in the hoppers at sub-zero temperature in order to retard the age hardening process. Frost formation on the rivets is effectively prevented by purging the enclosure with gaseous nitrogen. Upon passing through the coolant coils, the nitrogen absorbs sufficient heat to convert it from the liquid state to a gaseous state. The gas then discharges from the open end of the coils into the enclosure and through a vent in the side wall of the enclosure to atmosphere. To augment frost prevention, dry nitrogen gas is utilized to propel the rivets from the hoppers into the fingers of the riveting machine. Down time for servicing, changing rivets, etc. is reduced to a minimum by a temperature controlled space heater mounted inside the enclosure.

Abstract: Anode shields are provided around the anode baskets in an electroforming process.

Abstract: A molded plastic waveguide filter having a substantially U-shaped filter body with integral tuning posts shorter than the walls thereof and a substantially flat filter cap affixed to the walls of the filter body.

Abstract: System and apparatus for the controlled etching of copper work pieces with ferric chloride etchants. The working solution is constantly monitored with regard to its oxidation reduction potential (ORP) by comparison with a standard solution or voltage. To reduce the build up of etched copper in the working solution, an ORP controller activates the removal of specific quantities of that solution which are then replaced in precise stoichiometric proportions with fresh etchant. Simultaneously, oxidant is injected into the fluid to reoxidize ferrous ions to ferric ions. The solution is constantly monitored and the ORP control means repeats the above procedure as often as necessary to maintain the ORP of the fluid within an acceptable range.

Abstract: An accessory for riveting machines, replacing the conventional lower anvil, which permits both the top and bottom exposed surfaces of a laminated assembly to be countersunk and flush riveted. It includes a selectively and sequentially engageable sheet clamping means, countersinking means, rivet anvil, and rivet squeezing means.

Abstract: A functionally improved tape-like, heterogeneous, strip material for use in the fabrication of laminated structural shapes having high value of Young's Modulus and high tensile strength, comprising collocated, unidirectional, tectonic filaments such as graphite, boron, silicon-carbide, S-glass and E-glass, embodied in planar concourse, into an organic, thermosetting resin matrix or sheath such as an epoxy or polyimide base polymer forming a basal tract having at least one integral marginal tract of differing physical character so that a relatively lower Young's Modulus is exhibited by the material comprising the marginal tract than that exhibited by the basal tract. This difference in structural characteristic serves to provide an inherent arrestment barrier against fast rupture propagation of fractures which may develop in the basal tract material when the composite strip is subjected to sustained overload or external damage.

Abstract: A digital phase locked loop circuit for use in synchronizing output timing pulses with the positive going zero-crossings of an input data signal by quantitizing the input analog data signal as digital information, storing the digital information at given times by timing pulses, pre-programming a counter with a count corresponding to the quantitized digital information stored, and advancing or lagging an updated timing pulse in accordance with the timed count of the program counter which count is synchronized with the zero-crossings of the input data signal, whereby the updated timing pulses move to synchronism with the zero-crossings of the input data signal.

Abstract: An aircraft having a composite configuration comprising a conventional fuselage forebody portion which symmetrically and variformly blends into a relatively wide, substantially flat beaver-tail-like afterbody, with the afterbody having an integral pitch trimming camber and a composite pitch control device and air brake, hinged transversely thereacross and forming at least a part of its trailing edge. The beaver-tail afterbody is geometrically blended into and joined with the after portion of the conventional forebody through the medium of an intervening medial body defined by a geometric transition piece. The composite aircraft is further capable of fixedly accommodating any type of conventional wing configuration without the necessity for any adaptative, structural change or modification and also carries conventional propulsion units and control surface components.

Abstract: A high strength frusto-conical or conical structure utilizing an integral flanged reinforcing grid is disclosed. The structure comprises a skin plate having a generally conical shape, with a plurality of upstanding integral ribs. At least some of the ribs are configured in evenly spaced right and left spirals. Other ribs may extend along conic generatrix intersecting the spiral ribs at points where right and left spiral ribs intersect. Each rib includes a narrow flange at the inner edge, lying substantially parallel to the skin.

Abstract: A method and apparatus for measuring the porosity or density of a porous structure surface is disclosed. A controlled quantity of volatile liquid is applied to a porous surface and is allowed to evaporate. The temperature at the surface reaches equilibrium at the point necessary to supply the latent heat of vaporization of the liquid. This equilibrium temperature depends on the evaporation rate, which has been found to be a function of surface porosity. The porosimeter substantially eliminates other factors influencing evaporation rate, and measures and records the temperature at the surface. Once calibrated with samples of known porosity, this system is capable of making rapid, accurate surface porosity measurements.

Abstract: Apparatus is described for laying down structural members having cross sections of substantial depth, such as T-beams. Means are provided defining at least one recess into which the member is received in an upright position. An outgoing conveyor is provided for moving the member in a direction away from the recess defining means. The recess defining means is rotated about a substantially horizontal axis which lies in a plane normal to the direction of movement of the outgoing conveyor to move a portion of the member which projects from the recess into engagement with the conveyor to be moved out of the recess.

Abstract: Disclosed is a spear having an elongated rod to penetrate hard targets. The spear is delivered either from the air or the ground and is accelerated by a rocket motor to achieve the required impact velocity, for penetration.

Abstract: The transmission requirements for digital information representing images, such as radar displays produced by radar video returns and business letters, are reduced by encoding successive sets of duplicate data in the form of N-bit words which represent the data, each suffixed by an M-bit portion of a K-bit word representing the number of duplicate N-bit words. The output words, consisting of the M and N bit portions, are generated until all non-zero portions of the K-bit words are accounted for. The number of output words adapt to the run length of duplicate data words and provide for data compression; thus reducing transmission bandwidth requirements.

Abstract: Flow control for a cryostat in which the refrigerant flow rate is controlled by adding a contaminant to the refrigerant.