Abstract: An instrument mounting apparatus includes a bracket into which the instrument is inserted, a washer which slides over the instrument and dimensioned to hold the instrument, and a nut which also slides over the instrument. The bracket has key slots for accepting keys extending from the washer and has threads on the outer surface which mate with threads on the inner surface of the nut. Radial slots in the nut permit the insertion of a rod for torquing the nut tight to the bracket, while tapped channels are provided for a inserting a set screw into the one most convenient.

Abstract: A terrain bias compensator for a Doppler navigation system utilizes an auxiliary beam with each beam of the Doppler system to form Doppler beam pairs. The axis of the auxiliary beam is slightly offset from the axis of the main beam and is positioned so that the two axes are in the same vertical plane. After slant range compensation, the amplitudes of the Doppler spectrum of each beam is averaged over a predetermined time interval. The difference between the mean amplitudes of the two beams is divided by the offset angle to establish an amplitude per degree correction factor which is applied to the main beam signal returns to establish a main beam amplitude corrected Doppler spectrum.

Abstract: A tuned additive mass to a body subjected to forced vibrations that reduces the vibration amplitudes. The mass is coupled to the body in a manner that establishes a node at the previous maximum response of the body to the applied forces. The mass is constructed to respond in a spring like manner so that vibration frequencies of the mass is tunable to provide counter vibrations in the vibration frequency band. Vibration amplitude reduction is establish by vibrations of the mass that are in phase oppositions of the body.

Abstract: A Passive Navigation System (PNS) provides continuous updating of position, velocity, and attitude information of a vehicle without recourse to radiating or external navigation aids. The system accurately computes navigation information with the utilization of gravity sensors, gravimetric maps, vertical position, and velocity measurements. Sensor and map data are optimally processed by real time filtering to compute the best position, velocity, and attitude of the vehicle. The products of measured gravity gradients and the velocity of the vehicle are integrated over time to obtain a north, east, down gravity vector components which are combined with corresponding components obtained from a vertical deflection map in a complementary filter. North and east components of the combination are compared with the corresponding components from the vertical deflection map, while the down component of the gravity is compared to the down value obtained from a gravimeter.

Abstract: A compact, light weight device for facilitating the retrieval of artificial flies from trees or other elevated objects includes a hook which may be coated with a soft non-slip material coupled to a quick release strap, which may be made of "hook and loop" material, and a strong line. The strap is wrapped around a pole to position the hook. The pole may be removed from the release strap before the line is pulled to facilitate the object retrieval. A tube with one open and one closed end may be coupled to hook. A pole or the tip of a fly rod may be inserted into the tube to position the hook. This pole or fly rod may be removed after the hook is positioned.

Abstract: A terrain bias compensator for a Doppler navigation system utilizes an auxiliary beam with each beam of the Doppler system to form Doppler beam pairs. The axis of the auxiliary beam is slightly offset from the axis of the main beam and is positioned so that the two axes are in the same vertical plane. After slant range compensation, the amplitudes of the Doppler spectrum of each beam is averaged over a predetermined time interval. The difference between the mean amplitudes of the two beams is divided by the offset angle to establish an amplitude per degree correction factor which is applied to the main beam signal returns to establish a main beam amplitude corrected Doppler spectrum.

Abstract: A Passive Navigation System (PNS) provides continuous updating of position, velocity, and attitude information of a vehicle without recourse to radiating or external navigation aids. The system accurately computes navigation information with the utilization of gravity sensors, gravimetric maps, vertical position, and velocity measurements. Sensor and map data are optimally processed by real time filtering to compute the best position, velocity, and attitude of the vehicle. The products of measured gravity gradients and the velocity of the vehicle are integrated over time to obtain a north, east, down gravity vector components which are combined with corresponding components obtained from a vertical deflection map in a complementary filter. North and east components of the combination are compared with the corresponding components from the vertical deflection map, while the down component of the gravity is compared to the down value obtained from a gravimeter.

Abstract: A wave reflecting dish is constructed to provide a one piece unit having a hollow, watertight region between a first external surface having a paraboloidal contour and a second external surface which includes a base. Heater elements are positioned in the hollow region on a surface opposite the first external surface. Insulating material cover the heater elements and the hollow region is filled with a foam material. Snow, ice, and water drainage from the first surface is provided through a hole which extends through the unit from the first surface to the second surface. Provisions for mounting wave emitting and receiving apparatus are provided within the first surface. Attachment pads for mounting the dish on an external structure are provided on the base.

Abstract: A power amplifier includes a plurality of signal amplifying stages. An amplitude compensator positioned prior to the ultimate signal amplifying stage equalizes the signal amplitudes in the frequency band of interest to provide a substantially flat frequency response. Fail-soft operation is established by providing switchably redundant amplifiers. When an operating amplifier is detected as failing, automatic switching is performed to replace the failing unit with an identical unit to maintain amplifier operation. High-power amplification is accomplished by splitting a preamplified signal into a plurality of signals, amplifying the lower level signals so obtained, and then recombining the amplified signals.

Abstract: A beam sharpened, low sidelobe antenna is obtained by segmenting the antenna to provide two sub-antennas, one of which is arranged as an interferometer. The output signals of the two antennas are added and subtracted to provide sum and difference signals. The sum and difference signals and the output signals are then utilized to provide the desired beam sharpened, low sidelobe antenna.

Abstract: A method for heating pipes with closely spaced end portions that are to be joined by forge welding or the like. Two diametrically opposed contacts are attached to each end portion for supplying high frequency alternating current for resistance heating of the material in the respective end portions. The contacts for one of the pipes being located in close proximity to and substantially in the same axial plane as the contacts for the other pipe. The contacts for one of the pipes are arranged to form an angle (.alpha.) with juxtaposed contacts of the other pipe so that the projections of the juxtaposed contacts onto the axial plane intersect.

Abstract: Apparatus for linearizing the sweep frequency output of an FMCW radar employing a voltage controlled oscillator includes means for comparing a series of reference voltages sequentially with the instantaeous oscillator drive voltge, accumulating the individual resultant error voltages throughout successive sweep cycles, sequentially converting the individual accumulated voltages to exponential form and feeding the exponential voltages back into the drive circuit for the VCO.

Abstract: A rigid plate with an aperture therethrough has a variable coupler fiber optic sensor encapsulated in the aperture by an encapsulant having an index of refraction that varies with applied stress. Incident light applied to an input fiber of the coupler is coupled to the output fibers thereof in a ratio dependent on the stress applied to the encapsulant. In an alternative embodiment, a well in a member superposed with respect to the plate is filled with a low bulk modulus material which abuts the encapsulant.

Abstract: An acoustic baffle for reflecting sound waves and rejecting background interference noise for use with a hydrophone array. The baffle utilizes a plurality of lenticular resilient elements embedded in a compliant foam elastomer compound. The embedded elements provide control of overall baffle compliance for submarine applications, particularly for high hydrostatic pressure operation. The resilient members are formed from pairs of resilient lenticular shaped elements which are integrally bonded to a highly damped constrained viscoelastic layer to provide uniform noise reduction performance over a broad frequency range. The pairs of elements are joined at their ends by compliant end caps which provide minimum constraint on the motion of the ends, thus limiting bending stresses in the elements.

Abstract: Two Sagnac interferometers are mounted on board a ship with their axes in a horizontal plane. The axis of one interferometer is aligned in a fore-aft direction whereas the axis of the other interferometer is aligned athwartship. The output signals of the two interferometers are combined mathematically so as to cancel the effects of the ship's latitude and thus provide an output signal independent of this parameter.

Abstract: A coupler for crossing striplines which would otherwise intersect in a region of the substrate includes an electrically conducting housing through which transmission lines are passed that couple ends of the crossing striplines, formed by removing the cross-over region on the substrate. The housing is coupled to the stripline ground plane and provides ground planes for the coupling transmission lines.

Abstract: A reading guide includes first and second reading directors oppositely positioned at terminating ends of the reading guide. A separation section having a predetermined separation length, on the longitudinal axis of the reading guide, separates the reading directors. Both directors have beveled end edges, the first director having an end edge width which is less than the end edge width of the second director. The beveled end edge of the first director is formed by a double taper, the angles of the two tapers with respect to the longitudinal axis being unequal. Similarly, the beveled end edge of the second director is formed by a double taper, the angles of these two tapers with respect to the longitudinal axis, however, are equal. In the separation region the reading guide has curved sides, which may be sections of a circular, ellipse, or any other curve, which extend the length of the separation region.

Abstract: An antenna for inertialess scanning a beam through 360 degrees or any desired sector thereof. A reflector, in the shape of a truncated cone that is tangential to an imaginary sphere in the central plane of the cone, is positioned above a feed array located in the equatorial plane of the sphere. The feed array is fed by a network with a plurality of input ports, each of which corresponds to a beam in space. By successively energizing these input ports the beam is caused to scan continuously over the desired sector.

Abstract: A solid state amplifier for a microwave transmitter includes a power divider wherein a signal to be amplified is divided into signals of equal signal levels. The equal level signals are respectively coupled to a plurality of amplifiers wherefrom the amplified signals are coupled to a combiner wherein the amplified signals are added and signal sum provided at an output terminal of the combiner. Each of the amplifiers may be comprised of a first stage amplifier, the output signal of which is coupled to a multiplicity of component amplifiers which, in tern, are coupled to a the output terminal of the first stage amplifier via a second power divider wherefrom signals of equal level are provided to the component amplifiers. Bias voltages are provided to the amplifiers via a modularized power supply having some modules with redundant converters.

Abstract: Commutation switches for electronically scanning cylindrical arrays are disclosed. One embodiment reduces the number of transfer switches needed in a commutation switch by utilizing the commutation inversion property inherent to transfer switches having a binary number of input and output ports. A second embodiment having inversion capability provides a transfer switch with non-binary number of input and output ports. Commutation switches employing transfer switches of the second embodiment exhibit reduced complexity over the prior art and provide lower signal loss than that achievable with commutation switches of the prior art.