Abstract: A fire extinguisher of compact, self-contained character is installed in electrical equipment by being mounted within an aperture of a housing for the equipment. The extinguisher has an elongated vessel for containing under pressure a fire extinguishing substance such as halogenated hydrocarbon type. A nozzle is carried at one end of the vessel and is closed by fusible material which melts at a predetermined temperature to permit discharge into the housing. The nozzle is formed as part of a fitting which carries a washer-like disc having an adhesive substance on it to permit adhesive securement of the extinguisher to the equipment housing, with the greatest portion of the vessel extending exteriorly of the housing and only a small portion of the extinguisher thus extending interiorly of the housing. The vessel has a relatively high aspect ratio, such as permitting it to be installed in an aperture defined by an electrical knock-out.

Abstract: An apparatus for transporting a spacecraft and fluid propellant from the earth to a substantially low gravity environment above the earth with substantially reduced loading of the spacecraft due to forces upon the fluid propellant during the transport, the apparatus including a vehicle for carrying the spacecraft and the fluid propellant from the earth to a substantially low gravity environment above the earth; a plurality of external tanks disposed within the vehicle, external to the spacecraft, for containing the fluid propellant as the vehicle carries the spacecraft and the fluid propellant from the earth to the substantially low gravity environment above the earth; a plurality of spacecraft tanks disposed within the spacecraft for receiving the fluid propellant and for containing the fluid propellant; and means for transferring the fluid propellant from the external tanks the spacecraft tanks in the substantially low gravity environment above the earth.

Abstract: The present invention provides an economical yet effective system for the protection of the command link of ground controlled beacon tracking satellites. The invention includes means for detecting the amplitude and/or phase modulation of a composite signal which results from the beating of an intruder's carrier signal with an uplink beacon. A bandpass filter is included for guaranteeing that the low frequency sweep of the beacon signal and the high frequency data communication signals are passed through the receiver without interference. The resulting output of the bandpass filter corresponds to the intruder's carrier. This signal is rectified to provide a DC signal. A first comparator is provided for comparing the output of the detector to a first threshold which gives an indication as to whether or not the intruder is attempting to saturate an intermediate frequency (IF) stage of the satellite's receiver. A second comparator is provided for comparing the above-identified DC signal to a second threshold.

Abstract: A modulator system for converting a three-channel input microwave signal to a single-channel output microwave signal is formed of two microwave sections which are joined together at both their inputs and their outputs by hybrid circuits, one of which serves as a power divider and the other which serves as a power combiner. Each of the microwave sections includes a pair of couplers which are joined by a Faraday rotator. First and second microwave input signals are applied to a first port of an input coupler in each of these sections. A third microwave signal is connected by the hybrid divider to a second input port in the input couplers of each of the microwave sections. Polarization of the third signal is vertical and is maintained through the two sections. Polarization of the first and second signals is horizontal and is maintained through the two sections.

Abstract: The method of recovering metal from a coated condition wherein the same is encased within polyvinyl chloride which comprises disposing the coated metal upon a mesh or other perforated support within a vessel, immersing the same in a bath of tetrahydrofuran under ambient conditions, then closing the vessel containing said mesh or perforated support and permitting the treated material to remain therein in immersed state for a period of time commensurate with the quantity of material to be de-coated and with the thickness of such coating. However, with customary coatings in the order of approximately 1/4" to 3/8", a period of about one hour is adequate and such should be relatively indicative of the periods of time necessary with thicker coatings.

Abstract: An antenna pointing control system primarily useful for aiming and controlling a communications satellite directional antenna. The invention makes use of a ground based pilot station which transmits an up-link signal to the satellite, including frequency differentiated communication signals and command and control signals. The command and control signals are referred to as the beacon or pilot signal. The pilot signal is a triangular frequency modulation waveform. The communications signals and the pilot signal are received by a common directional antenna on the satellite. A microwave network coupled to a multiple feed horn assembly of the antenna and responsive to the pilot signal produces pilot signal components including a sum signal and east-west and north-south error signals indicative of the corresponding angular errors between the desired antenna pointing direction and the direction from the satellite to the pilot station.

Abstract: A spacecraft specifically adapted for launch from the space shuttle by means of a cradle having locking and ejection mechanisms mounted therein. The cradle fastens into the payload bay of the space shuttle and returns therewith for reuse in subsequent launches. The spacecraft mounts at three points to the cradle, and the cradle mounts at three points to the shuttle such that a plane through the attachment points passes through the roll axis of the spacecraft at approximately the center of mass thereof. The cradle utilizes the truss structure of the spacecraft to produce the required stiffness by providing a structural tie between the two ends and the bottom of the cradle. At launch, the spacecraft is ejected with both linear and angular momentum, the spin providing gyroscopic stability. The locking mechanisms in the cradle can be remotely controlled to relock the spacecraft to the cradle in the event of an unsuccessful deployment attempt.

Abstract: A multiple channel microwave rotary joint is disclosed which is a toroidal cavity having first and second halves each with a bearing surface for rotation about the axis of the toroid. A plurality of input ports are mounted about the external cylindrical surface of the first half for generating a plurality of modes within the toroidal cavity. A first hybrid network is coupled to the inut ports for providing the proper phase input signals for generating the various modes. A second hybrid network is connected to a plurality of output probes mounted to the second half of the toroidal cavity. The rotary joint has a passageway which is axially aligned for allowing a plurality of multichannel rotary joints to be "stacked" and the interconnecting microwave cables or waveguides to pass through the passageways.

Abstract: A transmission system for use in a communications satellite is disclosed which utilizes a power divider providing equal power output from N output ports having a uniform phase progression from port to port, the sense of which depends upon which of two input ports is excited. In an illustrated embodiment, one input port generates a first sense of circular polarization and the other generates the opposite sense. The two oppositely polarized circular waves are applied to the multiphase power divider. The cylindrical-bodied power divider has N output ports, where N is an odd integer, arranged at 360.degree./N about the cylindrical surface. Disposed within the power divider is an N-bladed septa for providing power division and isolation. A 180.degree. phase inverter is connected to (N-1)/2 output ports for providing a wave having a phase progression of 180.degree./N from the power divider.

Abstract: A motor active nutation damping system employing a rotor mounted accelerometer, a platform/rotor relative rate sensor, a despin motor and a controller. In the presence of nutation, the accelerometer senses a sinusoidal acceleration whose amplitude is proportional to nutation angle and whose frequency is rotor nutation frequency, i.e., the rate at which the transverse angular momentum vector appears to rotate in rotor fixed coordinates. The controller multiplies the filtered accelerometer signal by a square wave at relative rate generated by the relative rate sensor to obtain a signal consisting of sinusoids at platform nutation frequency and higher order frequencies.

Abstract: An improved multiplexer especially adapted for combining a plurality of microwave signal channels for transmission over a common transmission path is disclosed. A single "directional filter" multiplexer structure is utilized to combine contiguous or adjacent channels without resort to odd-even channel separation or additional equalization and/or compensation networks. By purposely extending the bandpass characteristics of preselected channel filters so that either or both of their cutoff frequencies extend substantially past their associated channel band edges and well into the reflection loss regions of the adjacent channel or channels the adjacent channel mutual interaction effect is exploited.

Abstract: A spin-stabilized body having deployable solar panels or appendages is modified by making the deployment mechanism capable of partial retraction and extension from the normal deployed position on an individually commandable bais. The spin axis of a free spinning body is dependent upon the location of the center of gravity within the body rather than by external bearing or support points as with a restrained spinning body. However, mispositioning of the center of gravity of the spacecraft may cause misalignment of the spin axis with respect to the geometric axis, thereby causing dynamic imbalance which is observed as body wobble. Such wobble can be minimized by offsetting the center of gravity of the panels or appendages from the center of gravity of the spacecraft in the axial direction and making the deployment mechanism for the panels or appendages capable of partial retraction and extension in the radial direction on an individually commandable basis.

Abstract: A zero insertion/retraction force connector is disclosed in which a folded spring is mounted in a housing with the folded spring having an arched portion to one side, one end of which serves as a sliding pivot for an extension which curves back towards the arched portion. This extension forms a moveable contact which is deflected towards a conductive stripe on the edge of a printed circuit board when, in one embodiment, a printed circuit board is inserted into the connector such that the bottom of the printed circuit board depresses the arched portion of the spring. Depression of the arched portion causes the sliding pivot to move laterally and rotate such that the extension swings into contact with one side of the printed circuit board and slides upon the conductive stripe in a wiping action while pressing the other side of the board against a vertical wall of the connector to sandwich the printed circuit board between the moveable contact and the wall.