Abstract: An S-band standing wave electron accelerator structure having a multiplicity of resonant accelerating cavities and resonant coupling cavities mounted sequentially in an alternating accelerating cavity-coupling cavity pattern along an accelerator axis, with adjacent cavities separated by a common wall. The common walls and end walls of the structure have beam holes concentric with the axis, and the common walls further have two slots for coupling energy between the cavities. To prevent direct coupling between the accelerating cavities which are separated by a coupling cavity, the coupling slots in one wall of the coupling cavity are rotated approximately 90.degree. about the accelerator axis with respect to the coupling slos in the other wall. The structure is assembled by brazing a number of conductive segments together. Each segment forms half of each of the adjacent cavities having the common wall and thus consists of half of an accelerating cavity and half of a coupling cavity.

Abstract: A travelling-wave tube with improved heat dissipation characteristics, having a helical delay line disposed between an electron-beam generating system and an electron-beam receiver, with the helical delay line being supported by a plurality of retaining members, at least one of which is made out of a material different from the remaining members, the latter being made out of quartz and the first mentioned member being made of a material that has a better heat conducting capacity than the quartz rods, at least in radial direction, and has a dielectric constant that does not differ sufficiently from that of quartz to materially effect the gain of the tube or dispersion curve of the signal wave.

Abstract: The present invention relates to a backward wave mode travelling wave oscillator tube.The delay line is in two sections of dissimilar length, 40 and 42, aligned in the direction of propagation of the electron beam (the cross-hatched area); the second 42 being the shorter, receives the beam already modulated by the first, 40, operating in the backward wave mode. The load 8 is arranged at that end which is adjacent the electron-gun 1, 2, of the second delay line section, also operating in the backward wave mode.Application to the design of high-output backward wave tubes for operation in the millimetric sub-millimetric wavebands.

Abstract: A traveling wave tube employing a coupled-cavity type slow-wave circuit and having high gain and efficiency over a wide operating frequency band as a result of a design in which the slow-wave circuits are separated into first and second (i.e. fore) and output slow-wave circuits connected to one another by sever sections containing nonreflectivity terminated waveguides. The synchronizing frequency of one of the fore slow-wave circuits is selected to be different from that of the other fore slow-wave circuit and the output slow-wave circuit. The aforesaid slow-wave circuits incorporate coupler cavities at the opposite ends thereof and a plurality of main unit cavities positioned between the coupler cavities. The desired synchronizing frequencies are obtained by controlling the dimensions of the cavities, interaction gaps, apertures and coupling irises.

Abstract: A travelling wave tube is provided with a slow wave structure consisting of clover leaf cavities in which frequency selective attenuators are present in subsidiary cavities formed within the nose of a clover leaf cavity. Each attenuator consists of dielectric material loaded with attenuation material. The use of the invention enables the coupling properties of the clover leaf cavities and their resonant frequencies to be chosen to provide optimum oscillation suppression.

Abstract: A delay line for traveling wave tubes, in particular for the amplification of mm waves, has a wave guide which is provided with outward-leading transverse walls each of which has a central electron beam opening and at least one coupling opening and which form a line cell with the adjacent transverse wall. The delay line contains two portions having a different constant delay for the line wave, where the delay of the front line portion, considered in the direction of the electron beam, is lower than the delay of the rear line portion. A transition section is arranged between these two portions for matching and comprises a single matching cell in which at least one of the two transverse walls of the matching cell carries at least one matching pin which projects into the interior of the cell.

Abstract: A grounded cylindrical metallic housing is hermetically closed at one end and an electric insulation hermetically extends through the other closed end of the housing to form in the housing a space filled with an electrically insulating gas. An arrester element disposed in the space has the incoming-line side connected to a terminal extended and sealed through the insulation and the ground side electrically connected to the housing. The incoming-line side of the arrester element is surrounded by both the insulation and a shield ring embedded therein.

Abstract: Surge arrester spark gap assemblies for use within surge voltage arrester devices employ the gap electrode structure to direct the arc current flow.

Abstract: A spark gap protector includes a gas tube spark gap device received in a supporting base. A failsafe device for permanently shorting the spark gap protector to ground after an extended discharge includes a spring biased cage and a solder pellet. An extended surge current fuses the solder pellet resulting in movement of the shorting cage to a failsafe, shorted condition. The cage normally grasps a conducting ring spaced from a shorting contact member by a thin insulating spacer defining an auxiliary gap thereacross. In case the spark gap device vents so as to become substantially inoperative, and the cage does not operate to short the device, the auxiliary gap provided backup protection at a breakdown voltage somewhat greater than ordinarily supplied by the gas tube spark gap device.

Abstract: A traveling wave device having a slow wave structure formed from at least one casting in which at least a portion of the internal passages are formed during the casting process to provide a more rigid structure having improved dimensional retention through the elimination of a multiplicity of brazed joints at and between adjacent cavity walls.

Abstract: An accelerator for a linear beam of charged particles has a first accelerating section upstream which modulates and accelerates the dc beam. This section is a traveling-wave circuit through which the entire rf power flows from the driving source. Output power from the other end of the traveling-wave section flows through a transmission line to a standing wave accelerating section downstream of the input section. An attenuator and a phase shifter between the two sections allow adjustment in the energy added to the particles in the downstream standing-wave section without disturbing the synchronism of the beam with the upstream accelerating section. As a result a high efficiency of acceleration and narrow energy spread of the final accelerated beam are achieved over a wide range of particle energies.

Abstract: A traveling wave tube (TWT) has a slow wave structure (SWS) which is severed into two or more sections. A signal path, defined below, connects the end of an SWS section to the beginning of the following SWS section. The signal path comprises an impedance matching coupler (IMC), followed by an isolator, a variable phase shifter, and a second IMC. The aggregate band pass characteristic of the components in the signal path is chosen to reject, or strongly attenuate, all frequencies outside the desired operating frequency range of the TWT and yet pass, with minimal attenuation in the forward direction, all frequencies within the desired operating frequency range. The isolator is chosen to reject, or strongly attenuate, waves, of all frequencies, which propagate in the backward direction. The aggregate phase shift characteristic of the components in the signal path is chosen to apply signal power to the beginning of the following SWS section with the phase angle yielding maximum efficiency.

Abstract: A traveling-wave tube has a slow wave circuit consisting of a constant phase velocity section extending from the electron gun side of the tube, and a phase velocity tapering section extending from the collector side of the tube in which the phase velocity of the electromagnetic wave is lower than in the constant phase velocity section. An attenuator is located at about the center of the constant phase velocity section. The ratio of the length of the phase velocity tapering section to the distance between the end of the attenuator which faces the collector side of the tube and the electron gun side end of the phase velocity tapering section is equal to, or less than 0.4.

Abstract: Undesired oscillations are suppressed in high-power, high-frequency, multe meanderline printed circuit traveling wave tubes. .pi. point frequency oscillations of various modes are attenuated by providing resistive coated longitudinal gaps in the ground plane conductor. The gaps permit lower radio frequency currents to propagate along the length of the line while blocking transverse currents of higher .pi. mode frequencies. The resistive coatings and spacing of the gaps control losses while permitting improved operation at the desired frequency. Increased beam current is produced at the output collector due to elimination of oscillations.

Abstract: A travelling-wave tube comprises a delay line section, an electron collector comprising several electrodes in a cooling chamber, one end wall of which is connected to the delay line section, the several electrodes being individually mounted on an inner wall of the cooling chamber by insulation with good heat conduction characteristics and individually electrically connected to insulated bushings in the said end wall.

Abstract: A surge protector or arrester for providing surge protection for relatively low voltage or secondary equipment, circuits and systems includes a vertically stacked, parallel arrangement of two, independent, spark gap and valve block assemblies, the components of which are generally horizontally disposed within a triangularly shaped surge protector housing. The triangular shape of the housing enables maximum spacing of the three electrode contacts associated with the two assemblies to prevent their flashover while maintaining minimum exterior housing dimensions. The components of the two assemblies are disposed horizontally within the housing after a sealing and insulating compound has been applied to the entrance portions of the three contacts. Each of the three contacts includes an integrally formed crimp contact, an integrally formed lead-in electrode and an integrally formed spring contact.

Abstract: Backward-wave oscillations in a helix or helix-derived traveling-wave tube re prevented by dimensioning the conductive shell surrounding the helix so that the backward-wave space harmonic of the slow-wave interaction circuit has a cutoff frequency in the vicinity of the frequency of the potential backward-wave oscillations. Lossy material is disposed between the shell and helix so that there is strong coupling between the electromagnetic field and the lossy material near the cutoff frequency of the backward-wave space harmonic.

Abstract: A coupled cavity travelling wave tube is disclosed which has a sever including a termination wedge, a sever pole piece with a drift tube and a termination cavity member defining a rectangular waveguide. Disposed in the rectangular waveguide are preformed projections which are provided so as to engage with the termination wedge, the termination wedge thereby being sandwiched between the projections and the sever pole piece.

Abstract: An improved coupled cavity type traveling wave vacuum tube of the type containing serially spaced electromagnetically coupled cavities defined in spaces between serially spaced magnetic pole pieces, each of which contains magnetic ferrule portions projecting from the pole piece walls and bordering an electron beam passage through the pole piece, an electrically conductive nonmagnetic material of high thermal conductivity lines the inner walls of the ferrule, and in which a void formed in between the front and back side walls defining each pole piece is filled with a nonmagnetic material of a high thermal conductivity characteristic positioned in a thermal conducting relationship with said lining portion whereby the ability of the tube to dissipate heat generated therewithin during operation is enhanced and the tube may thereby be operated at higher duty cycles.

Abstract: The arrester comprises an insulating housing with end terminals and a plurality of varistors inside the housing electrically connected between the terminals. The varistors are provided individually or in groups with a heat transfer and sinking collar which is electrically insulating and thermally conducting. The collar may be in thermally conducting contact with the inside wall of the housing to improve heat dissipation to the housing. The configuration of the collar is such that when it is installed in the housing, there is a passageway through it to provide a longitudinal space in the arrester for accommodating arcing and for the venting of gas in the event of an arrester failure.

Abstract: A broadband electron beam deflection apparatus particularly for a tube in which its electron beam can be focused, varied in position and varied in intensity, consisting in the form of a pair of helices each having a flat surface adjacent to the optical axis of the electron beam and also being precisely maintained in a diverging direction to such axis over the length thereof is provided. The apparatus consists of two individual helix assemblies each composed of separate components combined into a single unit in a manner whereby symmetry and desired characteristic impedance is controlled by the dimensions of the helix and having an end-to-end propagation time equal to the electron beam velocity due to the pitch and circumference of the helix.

Abstract: Flat internal components of an arrester are stacked longitudinally inside the insulating housing cylinder with a perimeter portion contacting the inside wall of the housing. Each component has a guide channel extending longitudinally on its perimeter portion opposite the portion in contact with the wall. A resilient rolling bias member is disposed in the channel of each component in a deformed stressed state and forces the components laterally against the wall.

Abstract: The allowable gain of a crossed-field amplifier tube is increased by tapering the slow-wave interaction circuit to a smaller spatial period in the direction of circuit power flow. Concurrent variation of the electron beam drift velocity by tapering the dc electric or magnetic field further improves the gain and efficiency.

Abstract: Noise in reentrant-stream crossed-field amplifiers is suspected of being generated by electrons re-entering the interaction region with large amplitude cycloidal motion near the slow-wave circuit. Means to increase the electric field in a portion of the drift region preceding the circuit lowers the noise, presumably by collecting these electrons. The field may be increased by decreasing the spacing between cathode and drift electrode or by applying a bias voltage on an insulated electrode.

Abstract: An electrical arrester includes one or more pairs of electrodes disposed within quenching chambers which form current-limiting quenched spark gaps connected in series with an associated blow-out coil for magnetically influencing the arc in the quenching chambers. During the quenching operation, the blow-out coil is short-circuited and two different embodiments are disclosed for effecting this result. In one embodiment, the quenching chamber includes a short-circuiting electrode in the vicinity of that one of the electrodes of a pair which is conductively connected to one end of the blow-out coil and the other end of the latter is conductively connected to the short-circuiting electrode. In the other embodiment, the arrester includes a pair of auxiliary electrodes disposed within an auxiliary chamber and forming a by-pass spark gap connected in parallel with the blow-out coil.

Abstract: A delay line for traveling-wave tubes, particularly a wideband low-reflection attenuated line for millimeter waves, in the form of a hollow guide having successive transverse walls which define successive line cells, each of such walls having a central opening for the passage of the electron beam and at least one coupling opening, elongated attentuating members being disposed in the respective cells with their longitudinal axes extending parallel to the longitudinal axis of the delay line. The attenuating members are of like effective length and the matching cell lying immediately ahead of and/or behind the attenuating section of the tube contains, in each case, at least one matching member.

Abstract: The magnetic field produced by the periodic permanent magnets of a travelling wave tube is shaped to improve the transmission ratio of the electron beam. The first zero magnetic field occurs within the magnet region, and the first peak magnetic field occurs at the first minima of the diameter of the electron beam.

Abstract: A travelling wave tube having a periodic permanent magnetic focusing structure is provided with ferromagnetic plates having copper inserts which conduct heat away from the electron beam path and reduce the formation of hot spots.

Abstract: A traveling-wave amplifier tube adapted for use as a booster of transmitted signals has very small internal circuit attenuation so that it may be used without an electron beam as a transparent, passive path for low transmitter power. When the booster tube's beam is excited, the signal is amplified about 10dB. Upper bandedge instabilities in the lossless tube are inhibited by a lower cutoff frequency of the circuit near the output end than near the input end, so that bandedge power can flow both ways out of the large-signal output end.

Abstract: A current limiting spark gap for use in a valve type lightning or surge arrester includes a plurality of identical, mirror-image insulating gap plates assembled together to define arc elongation and cooling chambers between each pair of adjacent gap plates. Conductive electrodes are disposed on opposite sides of each gap plate. Dielectric rods extend through holes formed in the gap plates to vertically and horizontally align the gap plates in a vertical stack and to define and maintain the gap spacing between a pair of electrodes in each arc chamber. The spark gap utilizes only the electrode and arc chamber configurations to cause a follow current arc to move in each arc chamber to increase the length of the arc and to compress the arc against cooling walls and surfaces of the arc chambers. The electrode and arc chamber configurations achieve greater arc elongation and compression, and resultant cooling, to enhance follow current limitation.

Abstract: The invention relates to an arrangement comprising a traveling-wave tube mounted in a housing, and a power supply source enclosed by a separate housing.Inventively, all electrical supply lines inside the tube housing are run to a plug mounted in this housing, projecting outward and enclosed by a sleeve of electrically conductive material. The invention further provides for a central singular electrical coupling matrix in the power source, whereby all electrical connecting lines to the traveling-wave tube are combined and connected to the outside via one electrical socket carried by this housing. Both housings can easily be mounted such that, when the plug connection is established, the plug sleeve is compressed. The invention provides a space-savingly designed unit of traveling-wave tube and current supply unit connected to each other with an HF-seal.

Abstract: A traveling wave tube has a helical delay line which is supported by a plurality of dielectric support rods extending along the delay line. The delay line and support rods are housed within a metallic sleeve which has an enlarged diameter in the area of each end of the delay line. In this area at each end of the delay line a respective coupling conductor is connected to the delay line for supplying and discharging HF energy. In order to achieve a low reflection transition between the surge impedance of the delay line and that of the coupling conductor, in the region of at least one of the two ends of the delay line, a metallic matching component is provided which is peferably spot welded to a surface formed at the diameter enlargement, the matching component including an arm which is spot welded to that surface and projections extending from the arm radially inwardly between adjacent support rods and in close proximity to the delay line.

Abstract: An improved surge voltage arrester made up of a plurality of series arrays of magnetically blasted spark gaps arranged between two potentials with the gaps surrounded by a gas which increases their breakdown voltage, in which the connecting points of each two adjacent series arrays are connected through a control spark gap to the upper or lower potential with the control spark gaps surrounded by a gas which reduces their breakdown voltage.

Abstract: Travelling wave tubes designed to operate interchangeably at low power cw and high pulsed power have grids to gate the pulses and to switch the peak beam current between two values. To preserve optimum beam-focus conditions, the beam diameter should be simultaneously switched. A grid covering the central region of a concave cathode draws the low-current, small beam for cw operation or the central part of a large pulsed beam. A second grid controls added pulsed emission from the surrounding annular region of te cathode. To provide the proper ratio of beam sizes and uniform cathode loading, the cathode has radially varying radius of curvature. A hyperboloid of revolution is a good shape.

Abstract: A coupled cavity type traveling wave tube is provided with at least one sever termination means comprising a waveguide extending outwardly from one cavity. A ceramic type attenuator is brazed to the interior surface of one thin wall of the extending waveguide. A ceramic type plate is brazed to the exterior side of the same wall whose thickness is selected to permit the thin wall to undergo plastic deformation as a result of thermal deformation of the ceramic members. An enclosure wall is provided to surround at least the ceramic type plate. The enclosure wall is capable of maintaining a vacuum condition even in the case where the thin wall may develop a leak or hole.Two sever termination means may be provided. The sever termination means may be located on the same side of the coupled cavity type structure or they may be located on the same side and share a common dividing wall, said dividing wall being the aforementioned thin, plastically deformable wall.

Abstract: A system utilizing ionization produced by beams from laser and laser-like devices to pre-determine the course of stepped leader and lightning channel development, thereby affording protection of life and property. The applications of such a capacity to harmlessly discharge thunderclouds include forest fire prevention, protection of aircraft, protection of missiles and spacecraft (particularly at time of launch), protection of electric power transmission and distribution networks, protection of communication networks, and (to the extent that Vonnegut's electrical theory of tornadoes may be valid) reduction of the destructive force of tornadoes.

Abstract: A surge arrester for protecting telephone lines and the like from overvoltage has opposed carbon electrodes separated by an insulating spacer that houses one of the electrodes and provides a means for spacing the electrodes to define the arc gap therebetween. The other electrode has one round plateau with a flat end surface that defines one side of the gap. The plateau is surrounded by a valley structure which provides a maximum of relief or cavity space for carbon particles that erupt from the electrodes during discharge. The cavity space is used for venting erupted particles across the end of the spacer and thereby provides an increase in the surge life of the arrester.

Abstract: In the disclosed attenuation arrangement a plurality of axially extending boron nitride support rods having a substantially rectangular cross-section are disposed about the peripheral surface of a helical slow-wave structure. An attenuating coating is provided on the substantially radially extending opposing lateral surfaces of each rod, with the substantially circumferentially extending opposing lateral rod surfaces being free from attenuating material.

Abstract: As part of a microwave frequency device, such as a traveling wave tube, a novel slow wave structure is presented which comprises an electrically conductive wire formed into a series of interconnected loops which are spaced apart and parallel along a common axis, with said loops being arranged in alternate and intermediate pairs, the ones of said loops in said alternate pairs extending clockwise about said common axis and with the ones of said loops in said intermediate pairs extending counterclockwise about said axis and interconnecting portions of said wires joining ends of adjacent loops together to define a series electrical path which progresses from one end of the wire to the other seriatim through all said loops.

Abstract: A broad-band, low-reflection energy coupling or decoupling with a coupled cavity line in a traveling wave tube, particularly high-efficiency traveling field tubes, in which a rectangular hollow conductor is not loaded, and has the opposed walls thereof, of minimum spacing and greatest width, tapering in a direction toward the delay line, with the spacing between such walls at the delay line being approximately that between adjacent transverse walls defining respective cells of the delay line, an inductive shield being provided within the hollow conductor and spaced from the line axis, the coupling opening at the hollow conductor having an open angle larger than the corresponding angle of the coupling openings in the transverse walls of adjacent line cells.

Abstract: Selectively damped travelling wave tubes having particularly periodically alternating magnetic field for guiding the electron beam comprise a delay line consisting of cells which are separated from each other by partitions and which are positioned one behind the other in the direction of beam travel. At least one resonator chamber is provided with damping material and coupled to at least one of the cells, the resonant frequency of the resonator chamber being at least almost equivalent to a predetermined interference frequency and each of the chamber resonators formed by a recess in a partition and its resonant frequency having the most energetic oscillation corresponding at least approximately to the frequency of an interference mode which is above the operational frequency band.

Abstract: A delay line for traveling wave tubes comprises a rectangular wave guide having cross members which perpendicularly protrude into the wave guide interior extending alternately from two sides facing each other of a first pair of inner wave guide walls. The wave guide inner wall includes a recess extending in the longitudinal direction of the wave guide and disposed symmetrically at both sides of the longitudinal extension of the cross members, at least in the area of their ends. Such a delay line construction provides for the provision of a magnet surrounding the line which may have a comparably small inside diameter.

Abstract: A surge protector or arrester for providing surge protection for relatively low voltage or secondary equipment, circuits and systems includes a vertically stacked, parallel arrangement of two, independent, spark gap and valve block assemblies, the components of which are generally horizontally disposed within a triangularly shaped surge protector housing. The triangular shape of the housing enables maximum spacing of the three electrode contacts associated with the two assemblies to prevent their flashover while maintaining minimum exterior housing dimensions. The components of the two assemblies are disposed horizontally within the housing after a sealing and insulating compound has been applied to the entrance portions of the three contacts. Each of the three contacts includes an integrally formed crimp contact, an integrally formed lead-in electrode and an integrally formed spring contact.

Abstract: A crossed-field device having a plurality of slow wave energy propagating structures, each with an associated cathode, requires relatively low voltage for operation to provide a high power output. Electron beam current control is achieved by means of RF drive signals. Periodic permanent magnet focusing is utilized.

Abstract: A microwave oscillator is provided having electron emissive means and a first surrounding resonant structure. The first structure is fabricated of a material capable of emitting secondary electrons. A second resonant structure surrounds the secondary electron emitter and microwave energy is generated by the interaction between the electrons and currents induced in the structure. The high degree of isolation between the first oscillator section and the second amplifying section results in the generation of stable oscillations relatively free of effects of load variations.

Abstract: An electron tube for use as a traveling-wave tube or the like comprises an longated housing having a central evacuated passageway therethrough and a plurality of annular magnets and circuit means supported within said housing at predetermined spaced locations along the length of said passageway within said housing. Preferably, the housing comprises a pair of generally semi-cylindrical mating ceramic substrate halves, each half including semi-annular grooves along the interior thereof which mate with respective semi-annular grooves of the other half to define annular grooves in which said magnets may be positioned or formed and annular portions of said circuit means may be deposited. Preferably, the respective ceramic substrate halves also have guide paths established therein for the reception of conductive material deposited therein to form the interconnecting portions of said circuit means.

Abstract: An electron collector for an electron beam tube, in particular a high performance transit time tube, employs a hollow member for receiving the electrons, which hollow member is surrounded by a metallic cooling sleeve which is grounded during operation of the tube and which is electrically insulated therefrom for an operating potential which deviates from the ground potential. The collector is particularly characterized in that it comprises a highly heat resistant material with a low vapor pressure (melting point at least approximately 2,000.degree.C) and apart from an insulating attachment in the area of its electron beam entry opening extends by forming a vacuum space completely free standing into the cooling sleeve. The cooling sleeve is blackened at its inner surface facing the collector and is permeated during operation by a coolant supplied from a forced cooling system.

Abstract: The arrester includes a valve section made up of high current-voltage characteristic exponent metal oxide varistor valve blocks having a relatively high capacitance and a series gap section made up of simple gap units, the gap section carrying less than about one fifth of the total arrester voltage during a discharge. The valve blocks of the valve section are each provided with a parallel-connected bleeder resistor to adjust the time constant of the valve section so that the faces of the valve blocks are returned to a common potential within a time interval of between about one and about two milliseconds for allowing sufficient deionization of arc gases without degrading multiple lightning surge performance.

Abstract: An arrester is provided in a staggered stack of two columns of elements alternately disposed at substantially 90.degree. with respect to each other in successive levels of the columns. Plates of conductive material are at the ends of the stack and between successive levels for electrically and mechanically securing arrester elements thereon with auxiliary capacitors and resistors located between selected plates.

Abstract: In the 2.pi./3 standing wave mode of energizing resonant cavities, a regular field pattern is set up between adjacent cavities which follows the sequence + (or -), - (or +) and zero. In the novel system of this invention, two series of cavities are used to form accelerating sections wherein the standing wave is propagated successively from one section to the other such that adjacent cavities in each of the sections have positive and negative fields and the resonant coupling cells between the sections have zero fields. This system is used in the acceleration of two beams by a single driving source or in a double track race-track microtron.