Abstract: A stabilized imaging system in which the lens assembly is fixed, and an electro-optic imager element is moveable to compensate for three-dimensional movements of the surrounding structure. Preferably the optical train also includes a movable prism, which can rotate the field of view in one plane. Rotation of the imager compensates for the image rotation caused by rotation of the prism.

Abstract: A high-speed floating point conversion apparatus and method are disclosed, with special reference to selectable conversion of "source" IEEE format numbers to any of the "destination" IBM, DEC, or SEL formats. In the preferred embodiment, the exponent is input to a shift control block. The exponent is converted to a different base, resulting in a remainder. The remainder of the exponent base conversion is input to the shift position control input of a shift register (preferably a barrel shifter) which has received the fraction (or mantissa) of the original floating point number. The fraction is shifted an amount necessary to compensate for the exponent's base conversion. The shift position control bits are available after a very short period of time, so that the shifting process of the barrel shifter is also completed quickly. The exponent and shifted fraction (or mantissa) are then input to format conversion units which format the data bitwise as necessary for a particular output format.

Abstract: An electro-optic system which is advantageous for low altitude, high speed aerial reconnaissance. A linear imager is movably positioned in the focal plane of a fixedly mounted wide-angle lens system. The fore-aft motion capability of the imager can be used to select an optimal viewing angle for recognition, for image motion compensation (to reduce smear), or for other functions.

Abstract: On-the-fly video processing to implement two-dimensional algorithms is performed without a frame buffer or random-access memory, by using CCD delay elements whose clock rate is controlled by a phase synchronizing loop, to achieve precise vertical alignment of pixels where the chosen algorithm requires.

Abstract: A frequency-hopping datalink and providing communication between a base station, relay unit and multiple remote units utilizes time-division multiplexing and transmits information signals containing information relevant to the next frequencies of transmission. Signals from the base station are transmitted on a first frequency to a relay unit which retransmits the signals on a second frequency to a group of remote units. The information signal from the base station contains information concerning the frequencies of the next transmission and the time slot allotted for the remote units to respond. The remote units respond back at the first frequency which is received by the relay unit and rebroadcast to the base station at the second frequency.

Abstract: A liquid filled differential pressure detector comprises two pressure sensors. Each sensor is constructed of one or more capsules, which are pairs of diaphragms sealed at their peripheries. The innermost diaphragms are interconnected by a tube which contains a rod assembly. The interior of the sensors and interconnection tube form a sealed volume filled with a incompressible liquid. The rod assembly contacts the outermost diaphragm of the sensors and is displaced by expansion and contraction of the capsules caused by a differential pressure change against the outer surface of the sensors. The motion of the rod assembly is transformed into an electrical signal to indicate the pressure measurement. The apparatus is symmetrical about the center point of the tube to reduce error caused by the fluid's thermal expansion by causing equal and opposite forces to cancel, thereby preventing motion of the rod assembly.

Abstract: An image sensor is disclosed which is capable of handling large amounts of signal charge with small shift registers. The image sensor includes photoelements 10 in which charge is accumulated in response to sensed conditions; electrically-controllable transfer gates 20 adjacent the photoelements 10 for controllably releasing the charge from the photoelements; vertical shift registers 30, separated from the photoelements 10 by the transfer gates 20, for receiving the charge from the photoelements, and a scan generator connected to the barrier 20 for supplying a series of pulses thereto, a group of pulses being required to release all of the charge accumulated in the photoelements 10.

Abstract: A thermal link provides a thermal path between a heat source and a heat sink which compensates for irregularities on the surface of the heat source and/or heat sink and/or nonuniformity in the spacing therebetween. One embodiment utilizes a spring metal device having a free arm which allows the link to align itself under low pressure so that it is in intimate contact with both the heat source and heat sink. Another embodiment utilizes an elastomeric material filled with thermally conducting particles to form a mat that has a plurality of raised sections having air spaces between each of the sections. The raised areas deform under low pressure by expanding laterally into the air spaces to conform to the space between the heat source and the heat sink.

Abstract: A thermal link provides a thermal path between a heat source and a heat sink which compensates for irregularities on the surface of the heat source and/or heat sink and/or nonuniformity in the spacing therebetween. One embodiment utilizes a spring metal device having a free arm which allows the link to align itself under low pressure so that it is in intimate contact with both the heat source and heat sink. Another embodiment utilizes an elastomeric material filled with thermally conducting particles to form a mat that has a plurality of raised sections having air spaces between each of the sections. The raised areas deform under low pressure by expanding laterally into the air spaces to conform to the space between the heat source and the heat sink.

Abstract: To energize an electromagnetic clutch or other electromagnetic device having a movable armature, a voltage is applied across the coil of the device to cause an initial current to flow therethrough. A current dip upon initial movement of the armature is detected, and in response, a substantially linearly increasing current is applied to the coil, establishing a controlled movement of the armature.

Abstract: A frequency and phase demodulating circuit provides direct frequency demodulation utilizing only addition, subtraction and multiplication steps. Division of signals is avoided, as is the need for a look-up table of trigonometric values corresponding to the results of such division. By maintaining a substantially constant input amplitude to a quadrature sampler, a number of approximations may be made without introduction of error. Compensation for actual signal variation, as well as for first order errors due to the approximation process of the invention, results in accurate frequency evaluation and avoids the necessity for differentiating an initial phase determination.

Abstract: A brake apparatus is provided for tape recorders, particularly of the coaxial reel type, in which a single brake pad, mounted on a brake arm, engages a pair of adjacent coaxially disposed drive wheels for coaxial tape reels. The brake arm is biased by a spring into braking engagement with the drive wheels. A solenoid is operable to withdraw the brake arm, thereby disengaging the brake, when energized. The solenoid is controlled to be energized whenever a drive motor for the tape reels is powered, and to be deenergized when the drive motor is not powered. The disclosed structure provides automatic braking for the tape reels whenever the drive motor loses power or is shut off, thus providing positive mechanical braking both in a power loss condition and in a parking condition for the tape reels.

Abstract: To mimimize the weight of a magnetic tape recorder chassis and cabinet assembly, a wire frame chassis (18) carrying printed circuit board guides (20) and connectors (22) is mounted to one side of a sand cast bezel (24), and polyurethane wall panels (16) are secured to the wire frame. A cabinet cover and underlying tape transport assembly are hinged to the bezel to enable pivoting away from the wire frame, exposing circuit boards for servicing. The "open air flow" characteristic of the wire frame chassis (18) helps cool critical electrical components.

Abstract: An X-ray or gamma-ray scintillation crystal used in a radiation-type thickness gauge is calibrated by irradiating the scintillation crystal at a high intensity and then abruptly lowering the intensity to a low level (e.g. 1/100 the high intensity level). The nonlinear response of the crystal due to after-glow and hysteresis is periodically measured and correlated with an ideal (e.g. linear) response function. The radiation level is then increased to its former high intensity and periodic measurements are made of the nonlinear response of the crystal. The correlated values are stored, for example, in a computer memory as a table of time dependent correction factors. The stored values are used to correlate a measured signal from the scintillation crystal regardless of the radiation intensity and the hysteresis of the crystal and without having to wait for the "afterglow" to disappear in order to make subsequent measurements.

Abstract: A technique is provided for simultaneously displaying on a television screen juxtaposed pictures from two independent image sources. The required picture compression is achieved by storing analog samples of the video signals in an analog memory at one frequency and retrieving the samples at a higher frequency for display. A 2 to 1 picture compression is attained, for example, by retrieving the samples at twice the frequency at which they are stored.

Abstract: To minimize the weight of a magnetic tape recorder chassis and cabinet assembly, a wire frame chassis (18) carrying printed circuit board guides (20) and connectors (22) is mounted to one side of a sand cast bezel (24), and polyurethane wall panels (16) are secured to the wire frame. A cabinet cover and underlying tape transport assembly are hinged to the bezel to enable pivoting away from the wire frame, exposing circuit boards for servicing. The "open air flow" characteristic of the wire frame chassis (18) helps cool critical electrical components.