Abstract: An improved drive for a satellite dish assembly. A flat, steel arc is fixedly connected at its two ends to the pivotal frame of the dish assembly, which steel arc is provided with a series of rows of mini-gear teeth on its outer surface. The steel arc is sandwiched between a rotatable knurled hub and a roller bearing, which knurled hub is provided with a series of rows of mini-diamond-shaped recesses for meshing engagement and forming of the gear teeth of the steel arc, in order to pivot the steel arc, and, therefore, the frame and dish mounted thereto, through a desired arc for aiming the satellite dish. The knurled hub is driven by a motor assembly, the motor assembly, knurled hub, and bearing being mounted to a free end of a cantilevered support arm, the other end of which is fixedly connected to a housing for the pivot shaft of the dish assembly about which the frame and satellite dish rotate for aiming purposes.

Abstract: A satellite transmission receiving antenna with unique mounting provisions for a recreational vehicle roof. A generally cylindrical collar extends upward from the vehicle roof and attaches to a load distributing panel under the collar and over the area of the vehicle roof for load distribution. A parabolic reflector is hinged along an edge to a generally horizontal turntable within the collar so that the reflector may be rotated to a concave downward position to act as a weather cover over the collar and also to provide smooth aerodynamic conditions during transport. Rotation of the turntable through a motor driven gear coupling to the turntable effects azimuth positioning of the antenna and elevation angle is set by a linear actuator.

Abstract: A conversion system for a controller for an antenna rotator which includes circuitry for generating an analog signal which varies as a function of the angular position of the antenna. The conversion system includes circuitry for converting the analog signal to a corresponding first digital signal representative of the angular position of the antenna relative to a first reference heading of the antenna. The conversion system also includes storage circuitry having a prestored table of digital values of angular positions of the antenna relative to a second reference heading of the antenna and which in response to the first digital signal produces a second digital signal corresponding to one of the prestored digital values, the second digital signal thereby being representative of the angular position of the antenna relative to the second reference heading. A digital display system and controller for an antenna rotator are also disclosed.

Abstract: A mechanical seeker for use in guided missiles utilizes two axes of rotation which are non-orthogonal to each other and to the longitudinal axis of the missile, and which converge at a point coincident with the center of mass of the antenna. This combination allows wide look angles of plus and minus 45 degrees or greater in a small envelope on the order of 5 inches or less in diameter.

Abstract: A gyratory device for mounting a parabolic antenna on a base or frame in which the gyratory part includes a tubular stationary part receiving a motor and drive connections within the tubular part, a sleeve surrounding the tubular part. Adjustable arms are provided to adjust the axis of the gyratory part relative to the rotary axis of the earth and to adjust the angle of the antenna on the sleeve.

Abstract: An antenna system wherein the feed assembly is rotated to provide spatial polarization stabilization with respect to vehicle movement so that orthogonal polarizations can be used simultaneously.

Abstract: A gimbal arrangement for supporting an antenna element steerable in pitch and yaw is shown to include a generally spherical bearing supporting such element, such bearing having a slot formed therein and aligned with the pitch axis to engage a pin affixed to the antenna element and a pitch and a yaw cam assembly independently actuable to steer the antenna element in pitch and yaw.

Abstract: An antenna for receiving satellite broadcast television reception only (TVRO) programming, includes a main reflector dish, a pivot tube for pivotally mounting the reflector dish from a support, and an integrally formed azimuth track and drive comprising an arcuate track bolted to the back of the reflector dish with a trolley drive which engages the pivotal mount to drive the reflector dish along the azimuth to move the dish from satellite to satellite. The integral track and drive rides freely in the vertical direction on the pivotal mount to permit adjustment of the declination and elevation of the main reflector dish without disassembly or removal of the azimuth track and drive.

Abstract: Apparatus for an earth station antenna is disclosed herein including a parabolic dish antenna pivotally carried on an upper support post mounted for rotation about a vertical axis. Pivotal linkage interconnects the antenna with the upper support post for rotation about a horizontal axis. Power drive is carried in the upper support post for pivoting the antenna about its horizontal axis via the linkage while separate power drive operably couples between the upper support post and a stationary lower post for rotating the upper support post and the antenna about the vertical axis. The lower end of the lower support post is provided with a mounting recess for insertably receiving the terminating end of an upright mounting stanchion.

Abstract: A non-continuous brush and commutator segment torquer motor having a single radial air gap. The motor can be placed on the opposite side of the gimbal center line of a payload. This arrangement minimizes torquer mass, as well as providing greater clearance for the gimbal payload to travel through larger angular excursions. Hence, all payloads which are gimbal mounted, such as radar antennas, can be located closer to the gimbal center and can be driven through larger look angles.

Abstract: A stabilization aid for a vehicle- or vessel-borne search unit comprises two servomechanisms for stabilizing the observation part (3) of the search unit about two mutually perpendicular axes (S.sub.1 and S.sub.2) mounted on the part of the search unit which rotates about the search axis (1). The stabilization aid comprises a computer (7) for determining, from the instantaneous angle of inclination (.alpha.) of the platform (2) supporting the search unit with respect to an earth-fixed reference axis and the instantaneous angular position (B) of the search unit about the search axis (1), measured in the plane of the platform (2), input signals for the servomechanisms. A portion of these input signals are compensating signals for the control errors in the servomechanisms.

Abstract: A polarized receiving apparatus in which there is provided a first waveguide for transmitting polarized signals and a second waveguide secured to the first for receiving polarized signals at one end thereof. An antenna means is provided having integrally formed portions including a receiver probe portion disposed in the second waveguide and extending generally axially of the second waveguide for receiving one polarization of the incident signal, a launch probe portion concentric with the axis of the first waveguide and extending generally axially of the first waveguide for launching said signal therein, and a drive portion intermediate the receiver and launch probe portions with said drive portions including a first gear. A drive source is supported in a housing member which defines the first waveguide and this drive source comprises at least a second gear adapted to mesh with the first gear for driving the antenna means.

Abstract: Satellite tracking system for use between a ground mount and a satellite dish antenna and including the main components of a gear drive, a worm gear driven by a gear motor, and a coupling shaft connected between the gear and brackets supporting the antenna. The worm gear drive includes a potentiometer connected thereto providing a controller signal input. Limit switches can be provided for limiting the rotation of the antenna between prescribed limits. The worm gear drive provides direct shaft drive for accurate rotation through wide angles.

Abstract: A pair of facing channel members, or a short length tube saddle about the upper end of a vertical post and pivotably mounts a rocker assembly in the form of back to back channel bars. A bolt projects across the top of the facing channel members or tubes to locate the rocker bar and facing channel member or tube on the top of a vertically upstanding post. Right angle ball and socket mounts within end plates joining the rocker assembly back to back channel bars have projecting bolts received within paired frame tangs projecting outwardly from an open frame rigidly mounted to the dish antenna. The upper frame tang bears a slot to permit declination adjustment. The sweep, azimuth and latitude axes intersect each other to provide the lowest possible center of gravity for the antenna mount and minimize the moment arms for the members forming the same to thereby provide a highly rigid, heavy wind resistant support for the dish type antenna.

Abstract: An antenna is pivoted on a mounting about a first axis (3) and is driven by a screw threaded drive member (5) to which it is pivoted about a second axis (4). The drive member (5) engages a drive mechanism (6) which is pivoted about a third axis (7) all the axes being parallel. At one position of adjustment (illustrated) the second and third axes (4,7) are in line with each other enabling the drive member (5) to be pivoted to the position shown in broken lines thereby doubling the size of the arc through which the antenna can be rotated.

Abstract: An arrangement for a vehicle- or vessel-borne surveillance apparatus is provided with a two-axis, vehicle- or vessel-borne gimbal system (2, 3) and a platform (4) suspended by said gimbal system (2, 3). The platform (4) can be stabilized about the orthogonal axes (AA', BB') of the gimbal system (2,3) with respect to an earth-fixed reference position. The surveillance apparatus (5) is mounted rotatably about an axis (6) perpendicular to the platform (4). The arrangement comprises two linear actuators (7), being mounted directly on the vehicle or vessel, but acting on the platform (4), to permit the above platform stabilization through a mutually equidirectional or opposite motion. The arrangement further comprises a mechanical, universal coupling to transmit the rotational motion produced by a drive mechanism (8), being mounted directly on the vehicle or vessel, to the surveillance apparatus (5).

Abstract: An apparatus for rotating and driving an antenna device in a radio transmitter and receiver which can simply increase and decrease the driving torque by variation in weight thereof. This apparatus comprises a rotary body rotatably mounted on a main housing and supporting the antenna device thereabove, and one or more driving units detachably mounted on the main housing. The rotary body is connected to an input gear rotatably provided on the main housing through a gear mechanism. Each of driving units has a driving source and a keyway gear connected through the gear mechanism, the keyway gear being meshed with the input gear when the driving unit is mounted on the main housing. Thereby, the driving torque required for rotation of the antenna device is adjusted by increase or decrease in number of the driving units.

Abstract: A device used as an electro-mechanical converter includes a body having a spherical outer surface, a structure peripherally surrounding the spherical body and electromagnetic means spatially located from the body to cause a rotational displacement of the body. The body is connected to a static support and all rotational motions are relative thereto.

Abstract: A motorized antenna mount for rotationally and pivotally supporting a satellite dish on a main vertical support pole. A base is adjustably mounted on the top of the support pole by a plurality of plumb bolts to compensate for any vertical misalignment of the pole. A motor housing is pivotally mounted on the base by a hinge and pair of curved pivot guide tracks. An electric motor is mounted in the motor housing and is connected to a drive gear through a gear reducer for rotating a turret which is mounted by a thrust bearing on turret mount attached to the top of the motor housing. The satellite dish is mounted on the end of a support arm which is pivotally adjustably mounted on the turret for declination angle control thereof. The turret has an internal arcuate-shaped gear track extending preferably 180.degree. about a central opening formed in the interior of the turret and engageable with the motor for rotating the turret drive gear.

Abstract: A motor-driven adjustable mounting structure for satellite T.V. dish antennae which operates to scan an in line of sight segment of a geostationary T.V. relay satellite orbit belt. The mounting structure includes a vertical mounting post, a universal levelling structure atop the post, a vertically extending body pivotally carried by the levelling structure on a horizontal axis, a head structure rotatably carried by and projecting upwardly from the body and including an antenna carrier structure carrying the antenna with its axis normal to the vertical axis of the body and turning axis of the head.

Abstract: A polarized receiving apparatus in which there is provided a first waveguide for transmitting polarized signals and a second waveguide secured to the first for receiving polarized signals at one end thereof. An antenna means is provided having integrally formed portions including a receiver probe portion disposed in the second waveguide and extending generally axially of the second waveguide for receiving one polarization of the incident signal, a launch probe portion concentric with the axis of the first waveguide and extending generally axially of the first waveguide for launching said signal therein, and a drive portion intermediate the receiver and launch probe portions with said drive portion including a first gear. A drive source is supported in a housing member which defines the first waveguide and this drive source comprises at least a second gear adapted to mesh with the first gear for driving the antenna means.

Abstract: An antenna apparatus has a first wire-like antenna element formed into a rectangular planar loop and a second antenna element which comprises two L-shaped plates electrically connected to the loop and mounted to a rectangular planar base member. The loop is hinged to the planar base member along long sides of the respective rectangles so that the angle between the planes of the loop and base member is adjustable. The base member pivots about an axis on a mount which can be secured to a television receiver.

Abstract: The central part of the nut of a gimbal mounting system for rotating a microwave antenna and the like is given a movement of elevation about the second axis (5) when the corresponding motor (II) is started-up and a circular movement about the first axis (3) orthogonal with the second axis when the corresponding motor (I) alone is started up, said circular movement automatically producing a movement of elevation about the second axis.

Abstract: In combination: a frame; an outer gimbal mounted in the frame for pivotal movement about a first axis; an inner gimbal mounted in the outer gimbal for pivotal movement about a second axis orthogonal to the first axis; a sensor having a longitudinal axis; apparatus mounting said sensor in the inner gimbal with the longitudinal axis orthogonal to said second axis; apparatus carried by the frame for causing rotation of the outer gimbal about the first axis; and apparatus carried in part by said frame and in part by said inner gimbal for causing rotation of the inner gimbal about the second axis.

Abstract: A lockable bearing apparatus for permitting rotation of adjacent members such as parts of an antenna mounting structure, wherein the adjacent members define circular bearing flanges surrounded and received by a coupling that can be tightened or loosened to lock or release the adjacent members. The coupling comprises an annular member defining an annular inwardly opening recess for receiving the flanges, and the flanges engage one another and are angled with respect to one another such that the coupling engages the flanges and urges them axially toward one another when the coupling is tightened. Stabilizing means for maintaining orientation of the adjacent members during rotation is disclosed, as well as means for selectively rotating the adjacent members with respect to one another. In the preferred embodiment for providing an azimuth axis in an antenna mounting structure, inexpensive sheet metal components are connected by the bearing apparatus embodying the invention.

Abstract: The present invention provides apparatus and method for mounting a plurality of vertically-spaced antennas (256 or 384) or other devices (262) to a tower (12) of the type having three tower legs (20a-20c), and for both separate and selective rotational positioning of the antennas or other devices. The preferred embodiment includes first (170 or 342), second (170 or 342), and third (204 or 320) support housings that are separately attached to the three tower legs, and an antenna-mounting ring (142 or 292) that circumscribes the tower, and that is rotatably attached to the support housings.

Abstract: The present invention provides an apparatus and a method for mounting and both separate and selective rotational positioning of a plurality of antennas, or search devices, that are attached to the face of a tower. The preferred embodiment includes an antenna-mounting ring, or search-device mounting ring (142) that is attached to the tower (12) by a plurality of support rollers (160, 186, or 219). The antenna-mounting ring is rotationally positioned by a drive motor (214), and by a friction drive element that is connected to the drive motor and that engages the antenna-mounting ring. Preferably, one of the support rollers serves as the friction drive element.

Abstract: The present invention provides an apparatus and a method for mounting and both separate and selective rotational positioning of a plurality of separate antennas, or search devices, on a single tower. Three of the preferred embodiments for use in mounting and rotationally positioning antennas or search devices include an antenna-mounting ring, or search-device mounting ring (142, 292, or 406) that is attached to the tower (12) by a plurality of support rollers (160, 219, or 306). The support rollers are operatively attached to the tower or to the antenna-mounting ring and supportingly engage a circumferential groove (150, 298, or 430) which is located in either the antenna-mounting ring, or in a tower-attaching ring (402) that is interposed between the antenna-mounting ring and the tower.

Abstract: The present invention provides an apparatus for mounting and both separate and selective rotational positioning of a plurality of separate antennas, or search devices, on a single tower of the type having a plurality of vertically-disposed tower legs (20a-20c) and having bracing (22) between adjacent pairs of the tower legs. The preferred embodiments include an antenna-mounting ring, or search-device mounting ring (142 or 406) that is attached to the tower (12) by a plurality of shaft-mounted support rollers (160, 219, or 306).

Abstract: An interconnect system from a combination gyro and pendulum weight passive stabilization system unit and an equipment platform, such as an antenna platform, whereby the platform is position stabilized in pitch and roll as controlled by the passive stabilization system unit. The interconnect system may take the form of a selsyn system used with a generator and a motor interconnected by multiple wire circuitry to permit location of a passive stabilization system unit at an ideal location in an ocean-going ship, such as in the epicenter region of the ship, with minimized pitch and roll acceleration forces, and with the antenna platform stabilized thereby ideally located for antenna purposes as much as hundreds of feet away from the passive stabilization system unit.

Abstract: A pedestal gimbal drive assembly includes a yoke and a cross shaft mounted for movement about separate orthogonal axes for affording a sensing platform for being driven by differential drive mechanism for sweeping a hemispherical segment. One embodiment of the drive means includes an endless cable drivingly connected by means of two separate reversible motors to a pair of fixed pulleys on the platform and trailed over a plurality of idler pulleys and operative to move the platform in the desired motion. An alternate embodiment includes a driven gear connected to the ring and a pair of bevelled gears connected to the driven gear and connected by link members to the two independent reversible motors.

Abstract: A radar system for continuously displaying target returns on a conventional television receiver. The radar includes a console connected to a rotating scanner unit through conventional slip rings. The scanner unit contains a radar antenna coupled to a receiver and transmitter, and a power supply generating a multitude of high-voltage and circuit supply voltages from AC power. A position transducer measures the rotary position of the scanner unit and triggers the transmitter as the scanner unit rotates. The return signal is thresholded to generate a video data signal, portions of which are sequentially stored in separate memory locations, each corresponding to a respective range. The set of video data in memory thus corresponds to targets within a predetermined range in a single direction.

Abstract: A gimbal assembly includes an outer arcuate yoke gimbal member mounted on rollers to rotate about its axis and an inner gimbal member includes a platform pivotally mounted in the yoke to rotate about a second axis. Two drive motors are separately and independently connected through independent cable drive assemblies to separate ones of the inner and outer gimbal members and functions either individually or together to rotate the gimbal members selectively or both together in a combination of motion. In one form, the two drive motors are co-axially mounted in the base of the gimbal assembly. In another form the gimbal drive motors are co-axially mounted with the outer housing of one motor forming the drive pulley for the other drive assembly. In another arrangement the motors are disposed on adjacent parallel axes with one drive motor for the inner gimbal having co-axially disposed drive pulleys for the drive cable.

Abstract: The invention provides an antenna having a large area reflector formed of a plurality of conductive slats of carbon fibre re-inforced plastics material having air gaps therebetween. The slats are mounted on a supporting and shaping framework which is of like material. The supporting and shaping framework is carried on a support structure of aluminium and between the aluminium and the support structure and the carbon fibre reinforced plastics material of the supporting and shaping framework is provided the intermediary material (e.g. titanium or stainless steel provided to reduce the effects of electrolytic corrosion.

Abstract: A correction method for transverse defocussing of paraboloid oriented relative to the source initially aligned with the focus consists of securing said paraboloid to first platform, articulating said first platform through hinge means jointed to second platform, itself articulated through further hinge means jointed to a stationary part, and then orienting said hinge means to said focus, while providing moving means for said platforms, said moving means being servocontrolled responsive to pointing error detector thereby to hold permanently said focus close to the source.Provision is also made of a parabolic antenna comprising means for carrying out said method. The system is applied to radio and TV broadcast apparatus aboard satellites.

Abstract: A scanning radar system having the capability of taking a number of succeve looks at the same range and angle resolution cells with several millisecond time intervals between looks. The scanning radar system includes a pulsed transmitter, a receiver, and an array of energy beam radiators having individual beam paths with associated centerlines. A commutator switch and a duplexer sequentially connect a different one of the radiators to the pulsed transmitter at the beginning of each pulse repetition period and to the receiver during the subsequent interval between pulsed transmissions. A motor rotates the array of radiators as a unit to cause the beam path centerlines to rotate and scan the field of view.

Abstract: A highly compact and lightweight 82 channel all banded VHF-UHF television antenna having three antenna elements wherein each element is the identical physical length and each element includes two half sections. Each antenna element is separated a predetermined distance from each other element wherein the predetermined distance is substantially less than one-tenth of the shortest wave length in the VHF band. A first set of coils are utilized to electrically lengthen the halves of the two elements for reception in the VHF band and a second set of coils are utilized to provide proper delays between the signals received by each antenna element so that when the signals are combined the signals are substantially additive and in phase. The antenna system includes a weatherproof housing containing a rotor, a preamplifier, and electronic circuitry.

Abstract: A gimbal assembly in which the outer gimbal member is an arcuate yoke mounted on rollers to rotate about one axis, and the inner gimbal member is a platform pivotally mounted in the yoke to rotate about a second orthogonal axis. Two motors are connected through a differential drive system to rotate either gimbal member selectively or both together in any combination of motions. In one form the differential drive is an endless cable extending around the outer gimbal member and around pulleys on the axis of the inner gimbal member. In a modified form the cable is crossed at one end to drive the inner gimbal member from both ends. In another form the differential drive includes split outer ring members driven individually by the two motors and coupled to the inner gimbal member by a rack and pinion drive.

Abstract: An antenna system including a single directional antenna having a single directional gain pattern for receiving electromagnetic waves in a certain direction. The orientation of the directional gain pattern is varied to vary the gain of the antenna in directions other than the certain direction in which electromagnetic waves are to be received. The gain is varied at a frequency higher than that of amplitude variations superimposed on the received electromagnetic waves while maintaining the gain substantially constant in the certain direction in which electromagnetic waves are to be received. The antenna gain variations in the directions other than the certain direction are effective to reduce the amplitude of received undesired electromagnetic waves and thereby diminish amplitude variations caused by these undesired electromagnetic waves.

Abstract: A gimbal assembly in which the outer gimbal member is an arcuate yoke mounted on rollers to rotate about one axis, and the inner gimbal member is a platform pivotally mounted in the yoke to rotate about a second orthogonal axis. Two motors are connected through a differential drive system to rotate either gimbal member selectively or both together in any combination of motions. In one form the differential drive is an endless cable extending around the outer gimbal member and around pulleys on the axis of the inner gimbal member. In a modified form the cable is crossed at one end to drive the inner gimbal member from both ends. In another form the differential drive includes split outer ring members driven individually by the two motors and coupled to the inner gimbal member by a rack and pinion drive.

Abstract: A large dish member for use as a solar collector, radar antenna or the like is mounted on a tripod structure on a first set of bearings which permit rotation about a polar or azimuth axis, and a second set of bearings which permit rotation about an elevation axis. Drive about the elevation axis is achieved by means of a linear actuator with elevation position being sensed by means of a position transducer such as a selsyn. Drive about the polar or azimuth axis is achieved by means of two motors, one for slow drive, the other for fast drive, both of these motors being coupled through a timing belt drive and worm gear reducer to a drive sprocket. The drive sprocket engages a chain which is welded to the rim of an arcuate spoked drive member in the form of a wheel segment, which is fixedly attached to the dish member and mounted for rotation on the support structure. A position selsyn is provided to sense azimuthal or polar position.

Abstract: A pedestal and gimbal assembly related to missile semi-active radar seekers or supporting three gyroscopes and functions as a reference platform to relate airframe attitude. This is mechanized by utilizing the two degrees of freedom gimbal for pitch and yaw and controlling the missile body roll axis for the third degree of freedom. Structure of the positioning system includes a pedestal having an inner gimbal assembly including a support for mounting the antenna assembly and the gyros. A yaw torque motor assembly is carried by the inner gimbal and is provided with a pair of output shafts for supporting the inner gimbal and controlling the yaw movement thereof. A pitch motor is housed in the pedestal and includes a drive pinion and a drive shaft. The drive pinion is connected to the drive shaft. The drive pinion and yaw motor operates to control the pitch movement of the antenna assembly.

Abstract: A system is provided for multistation remote position indication for remotely controlling and indicating the position of a motor driven positioning system, particularly an antenna rotor, at multiple locations utilizing a single pair of control wires to interconnect all remote control units. The system includes the generation of a symmetrical alternating polarity low frequency pulse train which is amplitude modulated by the position of the antenna, display of the antenna position by means of a polarity selective peak detecting voltmeter, and control of the antenna position by means of polarity selective current means through a synchronous detector and antenna drive motor control means.

Abstract: In a small satellite earth station a directional antenna is rocked about a single axis, corresponding to an oscillatory change in declination, but constant hour angle. The rocking is approximately sinusoidal and has a period of one sidereal day. In a preferred arrangement the antenna is mounted on a rocking axis pivot which is fixed at right angles to, and rotatable for adjustment about, a polar axis member. The polar axis member is set up parallel to the earth's axis and the pivot is rotated about the polar axis member to set the hour angle. The rocking of the antenna is achieved by a crank and tie-rod arrangement driven by a clock motor mounted on the polar axis member. The arrangement is particularly simple and will, when set up, track a synchronous satellite without needing frequent adjustment.

Abstract: The present invention relates to a radar sector scan apparatus which reves its direction of scan without causing large current spikes in the scan-producing motor. This result is achieved by switching off the motor before the instant at which the scan direction is reversed and letting the momentum of the antenna (attached to the motor shaft) continue the scan. Spring and bumper means are provided for slowing, stopping, and then reversing the scan while the motor is off. A switching arrangement is provided which switches off and switches on the motor at the appropriate times to effect smooth scanning and scan reversal. The invention also includes automatic start up logic.

Abstract: An adaptive interface circuit for use in coupling movement commands to a device utilizing linear actuators to control the rotational position of a rotatable member. Since the rotational position of the rotational member is not a linear function of the extension of the linear member, the rotational controller may be characterized as having a gear ratio which varies with the position of the rotatable member. The system includes an adaptive interface which modifies the gain of the movement commands in a manner designed to offset gear ratio changes so that the system as a whole will respond linearly to the movement commands. The system is described with particular reference to an antenna tracking system.

Abstract: The present invention relates to a scanning system comprising a three elet reflecting antenna, wherein two of the reflecting elements synchronously counter rotate about axes other than their optical axes in order to generate a linear scan.

Abstract: According to the present invention, radar rays are reflected off a rotating econdary reflector which is both tilted with respect to and synchronously translated, in simple harmonic motion, in a direction transverse to the axis of rotation of the secondary reflector. The combined effect of the tilting and translating of the secondary reflector is to produce a line scan when the rays from the secondary reflector are reflected off a primary reflector.

Abstract: An automatic direction finder wherein a loop antenna is fitted within a combined handle and index rotatably pivoted at the center of a direction dial, a gear of a diameter large enough is fixed to said index and a pinion meshing with said gear is connected through a frictional power transmission with a direct current servomotor to which an automatically controlled output of said antenna obtained from the output of said antenna is given.

Abstract: A power operated radar antenna assembly for airborne use in which an antenna carried on one end of a pair of rockable arms is balanced by a pair of motors at the opposite end of such arms; unified operation of which motors effects the rocking of the arms for elevation scanning movement of the antenna.