Abstract: A self-calibrating star tracker in which a light signal source located on the detector is reflected into the optics and redirected from the optics back onto the detector. In this manner, movement of the detector or optics from a known position can be sensed and calibration of the instrument can be conducted at any time (i.e., pre-flight or during the mission). The star tracker is contemplated to be used with an inertial guidance system and comprises a detector and optics.

Abstract: A method and apparatus designed and constructed to be used as an accessory on X-ray machines when making X-ray pictures on X-ray film of the lower extremities of the human body for the specific purpose of accurately measuring the long bones and the joint spacing. Also the analyzationand comparing of the long bones and joint spacings with each other.The radiographic attachment apparatus is a separate unit from the X-ray machine and is not attached as a part thereof, but used as an accessory by merely placing the apparatus in the center of the X-ray table under the lower extremities of the body when making the X-ray pictures.

Abstract: A process for radioelectrophotography, which comprises imparting a uniform electrostatic charge to the surface of a recording layer of an image-recording material and containing dispersed therein many cells and/or pores to cause a strong electric charge to act on the gas inside the cells and/or pores, and irradiating the recording layer with radiation carrying image information to imagewise remove the charge on the surface of the recording layer and form an electrostatic latent image.

Abstract: The disclosed invention involves radioactive inspection of tubular pipe passed rotatively and longitudinally relative to an inspection head. A beam of radiation is directed so as to intersect the pipe along a chord where the intersection is spaced a distance "d" on a horizontal radius from the pipe axis, the distance "d" being approximately 0.6 of the radius of the outer pipe wall. A diametrical beam of radiation can be used for comparison purposes.

Abstract: The invention relates to a liquid scintillation spectrometry process and apparatus permitting the analysis of samples having a quenching of the fluorescent efficiency resulting both from a color quenching and a chemical quenching. The invention makes it possible to measure a parameter B which gives the respective contributions of the two quenching types. According to the invention, parameter B is obtained in the following manner. A scintillation radiation produced by a standard fluorescent source placed in the vicinity of the sample to be measured is passed through the latter. This source comprises, for example, a solid scintillator exposed to an alpha or beta radiation source. The scintillation emitted by the standard source supplies an amplitude spectrum which is measured. One of the significant characteristics of this spectrum is determined, for example, the ratio of the counting rates in two different channels. This ratio gives parameter B.

Abstract: Structures for containing and supporting scintillator bodies are disclosed in which the optical output of the scintillator body is channeled by light reflective means to photoelectrically responsive devices mounted on the top and bottom of the detector array. In accordance with one embodiment of the invention, the internal surfaces of the collimating array are coated with either a diffuse or specular reflective coating. In accordance with another embodiment of the invention, the photoelectrically responsive transducers are located at the top and bottom of the array rather than at the rear. In accordance with another embodiment of the invention, reflective light channeling wedges are provided to improve spacing requirements for the photoelectrically responsive transducers. The scintillator structures of the present invention provide superior optical coupling to photoelectrically responsive devices.

Abstract: A method and apparatus for absolute activity determination of radionuclides, especially of low maximum energy pure beta-emitters as for instance .sup.3 H, .sup.63 Ni, .sup.14 C, .sup.35 S. The application of the invention can also be extended for activity determinations of other radionuclides, for example of those disintegrating through the electron capture. The method contemplates producing pulses of various multiples of coincidence simultaneously, and correlating the counts of the pulses to obtain a measure of the absolute activity. This is achieved by providing a scintillation head containing at least three photomultipliers optically coupled to the scintillator and the source whose activity is to be measured. The outputs of the photomultipliers are connected via amplifiers to coincidence gates having two and three inputs.

Abstract: A scanning apparatus for cross-sectional inspection equipment comprising a rotatable disc supporting an X-ray source and a detector. The rotation of this disc is quickly braked as a coil spring provided on a speed accelerating and reducing means is compressed. The start of rotation of this disc rapidly gains the required rotation speed by the recovering force of the same compressed coil spring. A cable extending from various devices including the X-ray source and the detector provided on the rotatable disc is releasably wound around a hollow drum provided on this disc. The rotation force produced in the rotatable disc by this cable is off-set by a rotation force applied in an opposite direction to this disc.

Abstract: A computer tomograph with a fan-shaped x-ray beam and two detector arrays. The two detector arrays are arranged in parallel and adjacent one another. Their lengths are dimensioned such that one detector array is suited for the head region, and the second, for the trunk (or body) region of the patient. The numbers of detectors of the detector arrays are equal, such that the division of the shorter detector array is finer than that of the longer one. There are connected, in parallel, to the input of the measured value converter two mutually corresponding detectors of the respective arrays. For each detector row, there is one light- and airproof chamber provided, and disposed between the two chambers and the two collimators there is a partition made of radiation-absorbing material.

Abstract: In an illustrative embodiment marks with dual x-ray permeable apertures are at three spaced locations on the mask and transmit x-ray beams which are directed obliquely to the semiconductor surface. In this case, the marks on the semiconductor disc may be formed by monocrystals shaped in conformity with the incident beam cross section and located so as to produce reflected x-ray beams which intersect correspondingly shaped further apertures of the respective dual aperture marks on the mask. Alternatively the beams may impinge on the surface of the semiconductor disc itself at an angle to produce reflection, with x-ray absorbing material surrounding each reflecting region. In either case the reflected beams as transmitted by the further apertures are detected as a measure of the degree of parallelism of the mask and semiconductor disc.

Abstract: A holder for mounting a radioactive foil comprising a coined stainless steel disc having an opening with a lip surrounding the opening and providing a shelf to support the foil, a counterbore portion adjacent the lip providing a chamber for receiving the foil, and a readily deformable portion remote from the lip for permitting deformation of the chamber wall inwardly to retain the foil in the counterbore. A holder-foil assembly is disclosed which consists of a radioactive foil mounted in the above-described holder.

Abstract: High storage density for spent nuclear fuel assemblies in a pool achieved by positioning fuel storage cells of high thermal neutron absorption materials in an upright configuration in a rack. The rack holds the cells at required pitch. Each cell carries an internal fuel assembly support, and most cells are vertically movable in the rack so that they rest on the pool bottom. Pool water circulation through the cells and around the fuel assemblies is permitted by circulation openings at the top and bottom of the cells above and below the fuel assemblies.

Abstract: A suction pyrometer radiation shield comprising an elongated first alumina refractory tube, a series of smaller alumina refractory tubes arranged around and bonded to the inside surface of said first tube forming central passageway, an outer fracture resistant alumina refractory tube surrounding said first tube and an alumina refractory washer closely surrounding said first tube in abutting contact with said outer alumina refractory tube.

Abstract: Apparatus for analyzing an image member such as a photographic film bearing an image to be printed and providing information as to the image area. The information may be utilized in determining initial ink key settings for a printing cylinder on which the image is to be printed. The image member is positioned on a support surface and a scanner assembly including a light source and light sensors scans the surface. Light transmission readings are taken from calibration film strips on the support surface and at positions on the support surface corresponding to the locations of the ink key columns of the printing cylinder. The data are calibrated and normalized using the calibration readings. The data are also corrected for the number of layers in the image member. Data from ink key columns which will not be utilized in printing the image analyzed are discarded. A procedure is provided for removing the effect on the data of any non-image material on the image member.

Abstract: Device for regulating the source of electric energy on a hybrid electric vehicle comprising at least an electric motor for driving the driving wheels of the vehicle and supplied with current by said source of energy and a generating set comprising a heat engine with which there is associated a current generator supplying current to said source of electric energy. This device comprises a circuit for determining the state of charge of the source of electric energy, a circuit for controlling the excitation winding of the generator of the generating set in accordance with the state of charge of said source, and a logic circuit for operating and stopping the heat engine and controlled by said circuit determining the state of charge of said source of electric energy.

Abstract: A switching apparatus adapted to be used with medium-voltage cable networks comprising switching units each of which is of the single-pole type and each of which includes an encapsulation adapted to be embedded directly in the soil and means for actuating the unit in response to a remote control.The switching apparatus is particularly suited for medium-voltage cable networks in cities where the erection of above-ground distribution facilities is undesirable and expensive. The switching units may, preferably, be designed as vacuum circuit breakers.

Abstract: A circuit for unilaterally scanning teletype characters wherein the characters are supplied to an integrating circuit and to an impulse circuit wherein the impulse circuit can be controlled by the step changes of a character. A comparator circuit receives the output of the integration circuit and assumes a definite condition with each step change through a switch which is controlled by the impulses of the impulse circuit and a reference signal is supplied to the comparator circuit and the reference signal can be adjusted according to the desired delay of the descending or ascending edge of the step changes in the characters.

Abstract: Apparatus for providing pulses at a rate limited by an input analog control signal. The analog control signal is compared to a ramp voltage, and an output pulse is generated when the ramp voltage reaches the control voltage level.

Abstract: Intermediate ram operated electromagnetically connects at least two cylinders to operate them reciprocally and drive a vehicle or the like.

Abstract: A multiple disk, pancake, self-fed brushless dc motor characterized by high power density has a variable number of interleaved, axially spaced rotor and stator disks. The annular rotor disks are made of high coercive force permanent magnets such as cobalt-samarium and ferrites which do not demagnetize easily. The annular stator disks are yokeless and include a spirally wound laminated magnetic core made of steel strip or amorphous metal ribbon with opposing sets of stator slots and windings on both sides of the core. The permanent magnet machine can be operated as a generator.

Abstract: A low thermally conductive columbium metal stem has a heavy refractory metal x-ray target disk fastened to one end. A high thermal conductivity rotor hub comprising a cup-shaped element is fastened to the other end of the stem and the rotor hub is fastened to the end of an induction motor cylinder or liner which is coated to enhance heat emission and is induced to rotate by being coupled to a rotating magnetic field. A low thermally conductive bearing hub is fastened to the inside of the rotor hub and to a shaft which is journaled for rotation in bearings. The bearing hub enhances thermal isolation of the bearings from the hot rotor hub and hot target.

Abstract: The present invention provides an improvement in an apertured mask type color picture tube having a faceplate, a cathodoluminescent screen on the faceplate, a corrugated apertured mask adjacent the screen and an electron gun means for producing and directing a plurality of electron beams through the mask to impinge upon the screen. The mask is constructed by first forming the apertures therein and thereafter forming the mask in a corrugated shape. Aperture width in the apertured but unformed mask is adjusted to compensate for stretching and compression of the mask occurring during formation of the mask into a corrugated shape. Therefore, the corrugated mask is substantially free of aperture width variation from that desired caused by forming the mask in a corrugated shape.

Abstract: A magnetic circuit useful in crossed field tubes and the like. At least one permanent magnet assembly is provided which includes a high flux density magnet (as Alnico), a high coercive force magnet (as Samarium Cobalt) with an end area larger than the facing end of the high flux density magnet, and polarized oppositely thereto, and an iron transition member sandwiched between the two magnets. This isolates the high coercive force magnet and concentrates its flux. When used with a second such magnet assembly to create a high magnetic flux density in a gap therebetween, for example, in the interaction space of a crossed field tube, a higher flux density is achieved in the gap than would be the case utilizing the high flux density magnet alone within the available dimensional limitations. This is particularly so in an open magnetic circuit application having only a non-magnetic flux return path.

Abstract: A solenoidal electric field lamp comprises a plurality of toroidal ferrite cores connected to a radio frequency energy source and disposed in an ionizable gas. The cores are so connected and oriented that circulating discharge currents passing through each core produce magnetic dipole fields which tend to cancel one another. Near and far field electromagnetic interference is thus reduced even when the lamp is operated at higher, more efficient frequencies. The cores are disposed in a variety of configurations.

Abstract: A compact fluorescent lamp with a screw-in plug to fit conventional screw sockets which operates at 20-30 watts and provides the lumen output of a 75-100 watt lamp. The lamp is essentially a hollow cylinder with a glass envelope for the two outer walls. The space between the two outer walls is partitioned to constrain the arc discharge to follow a zigzag path around the surface of the lamp. The design parameters are such that the lumen output per square inch of phosphor is greater than from conventional tubular fluorescents. Efficiency is promoted by novel ballast design. The ballast fits into the hollow center of the lamp. The ballast is constructed of special shape to spread the arc within the evacuated glass envelope, thus reducing the current density and the total current, but maintaining the lumen output of the phosphor.

Abstract: Spurious electromagnetic radiation from an electrodeless fluorescent lamp having a phosphor-coated, globular glass envelope containing an ionizable gas surrounding at least a portion of a toroidal magnetic core is reduced by situating a conductive loop about the envelope such that the loop and core planes are normal to each other. The loop also acts as the harp for a lampshade. Radio frequency energy, coupled into the gas from the core to ionize and excite the gas to emit ultraviolet radiation and thus stimulate visible radiation from the phosphor, also radiates from the lamp. The loop, driven by the radiated radio frequency energy, creates an opposing electromagnetic field. Cancellation of the radiated radio frequency energy thus tends to occur at a distance from the lamp, sharply reducing electromagnetic interference from the lamp.

Abstract: Discharge lamps are connected to a commerical alternating current power supply through an impedance for blocking high frequency signals and an impedance compensating for the negative resistance of the discharge lamps. The discharge lamps are also connected to the commercial alternating current power supply through a rectifier and oscillator circuit, a voltage signal is generated including the commercial alternating current voltage superposed on a high-frequency, high-voltage signal from the oscillator. This voltage signal is applied to the discharge lamps to energize the same and maintain the lamps in a lighted condition.

Abstract: Circuit for providing low ripple DC power supply from a single-phase AC source without the use of a filter capacitor. The circuit comprises a high leakage reactance transformer with a primary winding and two secondary windings arranged with the secondary windings on opposite sides of the primary winding, a leading current circuit connected to one secondary winding and a lagging current circuit connected to the other secondary winding, and a three-phase full wave rectifier bridge connected to the leading and lagging current circuits to provide a low ripple DC power output. The DC power supply circuit is used with a pulse generating circuit to provide pulsed operation of a gaseous discharge lamp such as a high pressure sodium vapor lamp, and produces desirable relationship of lamp watts to lamp volts for improved lamp life and uniformity of illumination.

Abstract: A transformer particularly useful in conjunction with solid state high frequency push-pull inverter supplies for discharge lamps is disclosed. In accordance with one embodiment of the present invention, two E-shaped core sections are disposed adjacent to one another in a mirror image fashion with corresponding core legs aligned but with an air gap provided between the middle legs of the core structure. The transformer disclosed permits the use of non-bifilar winding methods in the manufacture of transformers particularly useful in square-wave push-pull inverters used in discharge lamp ballasting circuits. In addition, the core structure disclosed provides for an integral ballasting reactance which minimizes power loss induced in the surrounding metal casing or other nearby metal structures.

Abstract: A color picture display device having a circuit for generating a screen grid voltage derived from the line deflection generator, while the high tension generator is separated. Via a resistance element, the screen grid is coupled to a source which generates a parabolic voltage of the field frequency with a curvature opposite to that obtained by rectifying the line flyback pulses owing to the east-west modulation, the resistance element, for example a voltage-dependent resistor, having in operation, a dynamic resistance which is many times lower than the static resistance thereof.

Abstract: A limited rotation electromechanical torsional oscillator for driving a mirror in an optical deflection system. A drive armature is mounted on a torsion bar at the opposite end from the torsion bar support. The ends of the armature lie in an air gap between two pole pieces. The magnet flux in the gap is caused to vary by means of a drive winding which results in armature rotation. Resonant frequency is varied by adjustment of the length of the torsion bar and the flux density. Q is varied by means of resistance in series with the drive winding.

Abstract: There is disclosed a low mass, low inertia, low inductance armature motor having infinite point resolution and a high force to mass ratio. The basic configuration is a plurality of phase displaced armature windings 90.degree. phase displacement for even spaced increments and optimized linear force preferably on a non-conductive, non-magnetic substrate and sandwiched between an incremental, alternately polarized magnetic field or castellated single polarity pole structure. Each of the phase displaced windings is preferably driven by a simplified totem pole type switching circuit.

Abstract: An industrial robot comprises a robot structure having a movable part, driving means for driving said movable part, detection means for detecting substantially a displacement of said movable part and for generating a position detection signal, memory means for memorizing the signal from said detection means and reading out the signal thus memorized, control means for controlling a memorizing operation and reading out operation of said memory means and for controlling said driving means responsive to the signal read out from the memory means, workpiece conveying means for conveying a workpiece through a space in which said movable part of said robot structure moves, allowing working to said workpiece at a predetermined working place, and workpiece detection means disposed near entrance to the working place in a conveying path of said conveying means, and adapted to detect the workpiece conveyed to the working place and thereby to send out a detection signal to said control means, said control means undergoing

Abstract: The actual drive signals to a stepper motor which rotates a mechanical device provide low order bits used in place of the low order bits of a digital word derived from an analog position sensor, to provide an accurate feedback word for subtraction from a digital position command word so as to generate a position error signal to drive the stepper motor in a servo loop.

Abstract: A positioning motor is energized by an actuating signal which includes a component proportional to, and another component proportional to the time-derivative of the output signal of a displacement transducer. The displacement transducer includes a plurality of light detectors. A synchronizing structure coupled to the motor moves through the light paths of the light detectors, causing each to generate a respective one of a plurality of mutually phase-shifted first signal components. Signal-processing circuitry derives from the first signal components second signal components which are phase-shifted relative to the first signal components, and combines the first and second signal components to form the transducer output signal.

Abstract: A polyphase motor is disclosed in which each coil of the stator winding of, for example, a squirrel cage induction motor, is connected in series with a capacitor so that the capacitor, together with the input voltage, causes the stator core to periodically switch from a nonsaturated to a saturated condition and vice-versa so that the flux density is maintained at a uniform high level. A second set of stator coils may be provided which serves to provide increased starting torque and improve the overall operating characteristics of the motor.

Abstract: A switching regulator capable of performing open-loop functions. The inhet nature of the circuit provides a constant power translation regulator with short circuit dropout protection. Normal voltage or current regulation may be obtained by utilizing a control winding provided for that purpose. A free-running or locked blocking oscillator circuit in combination with a pulse width controlled switching regulator sustains its own drive and regulation functions. Measured efficiencies from 90 to 99 percent are obtainable with both resistive and line modulator type loads.

Abstract: A circuit arrangement for measuring the ratio of first and second capacitances of a capacitance displacement transducer. An alternating signal is developed the amplitude of which is proportional to the values of the first and second capacitances during respective first and second timing periods, the alternating signal being synchronously demodulated in one phase in the first period and in the opposite phase in the second period. The demodulated signal is integrated so that the integrator is charged and discharged during the first and second periods respectively, and the ratio of the discharge time to the charge time is equal to the ratio of the two capacitances. A digitized output is provided by means of a clock pulse generator and counter.

Abstract: Capacitance measuring device for measuring a physical quantity proportional or inversely proportional to the capacitance X of a first capacitor. A oscillating circuit includes a second capacitor having a reference capacitance X.sub.E or the first capacitor during successive reference and measuring phases under control switching network respectively. A counter counts a predetermined oscillation pulse number N.sub.E during the reference phase and a oscillation pulse number N.sub.X during the measuring phase. The duration of two phases are equal or in a predetermined ratio R by means of a counter-down-counter which counts and down-counts the same number of clock pulses at least a predetermined frequency. The change of the counting to down-counting condition is controlled by the counter when its count is equal to N.sub.E. The stopping of the counter is controlled by the counter-down-counter when its count is equal to zero at the end of the measuring phase.

Abstract: A circuit for ascertaining the direction of origin of the most significant transient appearing on a electrical power line within a predetermined interval is disclosed. Threshhold comparator circuit (325, 326) are provided to insure that transient polarities needed for the directivity determination are ascertained while the transient impulse is still rising towards its peak value. For any nominal, user-set threshhold (V.sub.2), a lower preliminary threshold (V.sub.1) is automatically set and when the transient exceeds the preliminary threshhold, the transient polarities are determined and correlated to effect a tentative directivity determination which is stored in an input latch (205). When the transient exceeds the nominal threshhold, the directivity determination is transferred to an output latch (211) to be read by an output printing device.

Abstract: A device for determining the blood sedimentation rate in a substantially vertical test tube, where the electrical or magnetic property of a given volume of liquid, which is changed by the settling of the erythrocytes in the test tube is measured as a function of time, by means of an oscillator with an output circuit which is completed via the column of liquid to be measured and by means of a measured-value pickup, having an output signal of which a pulse sequence of a definite frequency can be fed to a pulse counter with an indicating device.A coil-capacitor resonant circuit is coupled inductively with its coil or capacitively with its capacitor to liquid at a definite height in the test tube. An additional coil inductively coupled to the resonant-circuit coil serves as the measuring pickup. A retuning circuit is provided for the retuning of the resonance of the tuned L-C circuit which is detuned by the lowering of the boundary layer between the erythrocyte column and the plasma in the test tube.

Abstract: A detector apparatus for counterfeit paper currency comprising a clamp and torsion pendulum assembly for holding a note to be tested, a moveable magnetic field source mounted so that it can be brought into contact with the note and then withdrawn, and indicating means for detecting and measuring deflection of the note.

Abstract: To lock out certain channels in a scanning receiver, a counter in the scanning control circuit is manually stepped to the channel to be locked out and a signal is recorded in a memory at that point by depressing a switch while the memory is addressed by the circuitry which causes scanning. When the scanning circuit thereafter reaches the same channel, the address of that channel causes a readout from the memory which electronically inhibits the scanning of the locked-out channel. With minor modification, the circuitry may accommodate other electrically recorded switching operations such as band switching operations and priority operations.

Abstract: A device is provided for protection against the presence of transmission errors in an information transmission system used in railroading. An interrogation apparatus emits a periodically variable interrogation signal within a specified frequency band consisting of successive frequency ranges. A reply apparatus selectively dampens the interrogation signal in sub-ranges of each frequency range so as to provide a frequency-selectively reflected interrogation signal which has power penetrations in the respective sub-ranges. The first switching member is provided to produce a first impulse sequence whose impulses lie centrally at the border of the sub-ranges. A comparator then determines whether the center of the power penetration lies within one of the sub-range border impulses. If such is the case, an interference signal is activated. Similarly a second switching member is provided which produces a second impulse sequence having impulses wider than those of the first impulse sequence.

Abstract: In a digital information transmission system having an analog-to-digital converter (ADC), an information transmission medium, and a digital-to-analog converter (DAC) all located between a transmitting station and a receiving station, signal transmission is improved by injection of a controlled signal in the form of a symmetric triangle wave sweep having a maximum peak-to-peak amplitude exceeding the magnitude of a few quantization intervals of the ADC and the DAC, introducing frequency components concentrated outside the system frequency spectrum. A class of controlled signals is disclosed. In the preferred embodiment, the controlled signal is injected into the analog information input signal prior to conversion to digital form.

Abstract: Apparatus for and the method of simplifying and economizing upon transmitter power amplifier output stage circuitry is illustrated. By grounding the anode of the RF power amplifier, the FCC required plate voltage meter and plate current meters can be connected to near ground potentials and the requirements for a high voltage coupling capacitor between the anode and the antenna is eliminated. Although the specific embodiment illustrated uses a pulse-width modulated cathode modulation scheme, any type of cathode modulation will perform in accordance with the concepts of this invention.

Abstract: An electronic clock radio using a clock integrated circuit and a radio integrated circuit. A first energizing potential when applied to the NAP/SLEEP input connection of the clock circuit, causes the clock circuit to switch from a first electric state to a second electric state. After a selected interval of time, not greater than 60 minutes, the clock circuit switches from the second electric state to the first electric state. The radio, normally in an OFF state is placed in an ON state only upon receiving a second energizing potential applied to its input connection. A control circuit, having a manually operable switch with NAP and SLEEP positions and being responsive to the electric states of the clock circuit, connects this second energizing potential to the radio input only when:(i) the manually operable switch is in the NAP position and the clock circuit is the first electric state, or(ii) the manually operable switch is in the SLEEP position and the clock circuit is in the second electric state.

Abstract: A two-mode limited channel television receiver includes a memory address counter for scanning the locations of a limited position memory in response to generation of a channel number by a channel number counter. Channel numbers and corresponding tuning information may be programmed into and deleted from the limited location only memory. In the programmed channel mode, memory locations with programmed channel numbers are accessed in channel number order. In the skipped channel mode, only unprogrammed channel numbers are produced and displayed to the viewer. In a variation, all channel numbers, both programmed and unprogrammed are produced and displayed. Empty memory locations are automatically accessed when an unprogrammed channel number is generated.

Abstract: A dielectrically loaded four-port waveguide circulator is used with a reflected-wave maser connected to a second port between first and third ports to form one of a plurality of cascaded maser waveguide structures. The fourth port is connected to a waveguide loaded with microwave energy absorbing material. The third (output signal) port of one maser waveguide structure is connected by a waveguide loaded with dielectric material to the first (input) port of an adjacent maser waveguide structure, and the second port is connected to a reflected-wave maser by a matching transformer which passes the signal to be amplified into and out of the reflected-wavemaser and blocks pumping energy in the reflected-wave maser from entering the circulator. A number of cascaded maser waveguide structures may thus be housed in a relatively small volume of conductive material placed within a cryogenically cooled magnet assembly.

Abstract: Disclosed is a bias circuit of an amplifier for a microwave circuit, which amplifier is comprised of a pair of amplifier modules and at least one directional quadrature coupler having four ports including an isolation port, wherein the bias circuit is connected to the isolation port of the directional quadrature coupler.