Abstract: In order to achieve the above or other aims, according to one aspect of the present disclosure, a skin care device is provided which comprises: a body comprising a grip section for a user to hold, and a head section positioned at the end of the grip section; a plurality of skin-contacting plates positioned at the end of the head section; a plurality of oscillators for providing oscillations to each of the skin-contacting plates; and a control unit which supplies an electrical current to the skin-contacting plates and controls the oscillators, wherein the positive electrode and the negative electrode of the control unit are respectively connected to different skin-contacting plates.

Abstract: A spark plug includes a metal body member formed of a metal material, an insulating body member provided inside the metal body member and formed of an insulating material, a pair of central electrodes provided inside the insulating body member and having different polarities, and a ground electrode extending from the metal body member between a pair of central electrodes.

Abstract: A main field connection to connect to a main field winding has a semi-cylindrical portion with an axially thicker outer surface, an axially thinner inner surface, with an aperture. An extending portion extends from the semi-cylindrical portion to a remote extending end. The remote extending end extends for a first axial distance. The axially thicker portion of the semi-cylindrical portion extends for a second axial distance. A ratio of the first axial distance to the second axial distance is between 0.65 and 1.4. A rotating assembly, a generator and a method are also disclosed.

Abstract: A power management system includes a first power line, a second power line, a first parallel protector, a second parallel protector, a third parallel protector, a first current sensor, a second current sensor, a third current sensor, and a processor. The first parallel protector is coupled to the first power line. The second parallel protector is coupled to the first parallel protector and the second power line. The third parallel protector is coupled to the first parallel protector and a ground terminal. The first current sensor, the second current sensor and the third current sensor respectively sense a first current flowing through the first parallel protector, a second current flowing through the second parallel protector, and a third current flowing through the third parallel protector. The processor detects a surge discharging path according to the first current, the second current and/or the third current.

Abstract: A lightning protection system of an aircraft includes a wall defining an inner surface and an outer surface. The outer surface is configured to come into contact with a mass of air located around the aircraft. The lighting protection system also includes at least two electrically conductive lighting traps received in holes traversing the wall and at least one strip with pellets having an electrically insulating substrate and electrically conductive pellets spaced apart from one another on the electrically insulating substrate. The strip with pellets is fastened on the wall by the two lightning traps. The strip with pellets is attached on the inner surface of the wall.

Abstract: An add on device assembly for surge arresters used in substation, distribution and transmission applications that provides a means to electrically and mechanically disconnect a surge arrester at the end of life, such that it leaves a physical dimension between electrodes that is able to withstand normal system voltage and at the same time continue to provide surge protection until the arrester is replaced. The assembly contains a spring locking assembly that will lock a line spacing buss in an open position post isolator operation. The resultant gap is set to provide sufficient air insulation for system voltage and at the same sufficient surge protection for the system Basic Insulation Level.

Abstract: The present invention relates to a surge arrester for a charge controller of a battery. The surge arrester comprises a first voltage detector with a fixed predetermined response threshold and a second voltage detector with an adaptively adjustable voltage threshold. The voltage threshold of the second voltage detector is adapted as a function of the response of the first voltage detector.

Abstract: A voltage dependent resistor includes a ceramic body and an electrically conductive structure for external connection. The ceramic body has two opposite surfaces and a side surface connecting the two opposite surfaces, and at least one of the two opposite surfaces is formed with at least one protrusion at a position adjacent to the side surface. As the protrusion makes the opposite surfaces of the ceramic body non-planar, the voltage dependent resistor is capable of suppressing the occurrence of flashover firelight during surge impact, so that its capability of withstanding surge impact is enhanced and its lifespan is prolonged. In addition, such structural arrangement is capable of preventing ceramic plates from adhering with each other when they are stacked with each other during the sintering stage of a green compact, thereby simplifying the post-processing procedures and minimizing the defect rate.

Abstract: A multiple spark-gap arrester is disclosed. In an embodiment the arrester includes a series connection of a plurality of spark gaps between a first potential node and a reference-ground potential node and a trigger circuit having an input and an output, the input being coupled to a second potential node between two adjacent spark gaps of the plurality of spark gaps, and the output being coupled to at least one of the spark gaps between the second potential node and the reference-ground potential node, wherein the trigger circuit is configured, when at least one spark gap between the first potential node and the second potential node is ignited, to supply a trigger signal for the at least one of the spark gaps between the second potential node and the reference-ground potential node.

Abstract: A surge arrester for the power supply of low-voltage systems, having a housing, two electrodes which are situated axially opposite one another, an arc combustion chamber formed in the interior of the housing, and a trigger aid. A spark gap is formed between the two electrodes so that an arc is produced when the spark gap between the two electrodes is triggered, the axial distance between end faces of the two electrodes being so large that the arc voltage is greater than the expected line voltage. Conversion of energy within the surge arrester is reduced by the arc combustion chamber having an inner region and at least one expansion region into which the arc can propagate after triggering. The inner region is arranged between the two electrodes and is delimited axially by the end faces of the electrodes and is delimited longitudinally by the at least one expansion region.

Abstract: The invention relates to a spark gap having a plurality of individual spark gaps connected in series and present in a stacked arrangement, spaced apart from each other by insulating spacers (5) and nearly free of secondary current under typical operating conditions, wherein the individual spark gaps comprise electrodes (4) and outer connection electrodes are provided, and further having control elements for influencing the voltage distribution across the stacked arrangement and/or designed as an ignition aid. According to the invention, a mechanically pretensioned insulating element (8) can be inserted or pivoted between two adjacent electrodes (4) of the individual spark gaps, in order to interrupt the main current path of the spark gap in case of fault or overload.

Abstract: An electrical device that includes a first electrode and a second electrode that are separated from one another so as to form a gap structure. A layer of protective material spans the gap structure to contact the first electrode and the second electrode. A dimension of the gap structure, corresponding to a separation distance between the first electrode and the second electrode, is varied and includes a minimum separation distance that coincides with a critical path of the layer of protective material between the first electrode and the second electrode.

Abstract: An apparatus and method of operation of a low-current LED lighting circuit are disclosed. The invention utilizes high AC voltage input and unreduced voltage ripple component of the rectified DC power signal, which provides the ability to drive an LED load at high power factor at low current. The invention discloses both active and passive circuits to limit the peak current flowing to the LED and create a current source for the LED load. The proposed circuit increases reliability by optionally eliminating capacitor, inductor, and heatsink components while minimizing luminous flux fluctuations.

Abstract: Modular LED lighting systems can provide under-cabinet lighting. According to some embodiments, an LED lighting system may be provided with at least one LED light strip, a switch unit, and a removable electrical connector electrically connecting the at least one LED light strip to the switch unit in an end-to-end configuration. According to other embodiments, a modular under-cabinet LED lighting system may be provided having a plurality of LED light strip units having a female power receptacle at each end thereof, and at least one removable electrical connector received within respective female power receptacles at respective ends of an adjacent pair of the LED light strip units to electrically connect the pair of LED light strip units in series one to another in an end-to-end configuration. Because of the modular nature of the various components, a lighting system tailored to a specific under-cabinet lighting need can be provided.

Abstract: A tubular LED lighting fixture comprises: a heat sink shell; a printed circuit board supported on the shell and having an upper surface and a bottom surface, longitudinally extending laterally spaced wiring on the upper and bottom surfaces, and, transverse heat pipes running through the printed circuit board; a plurality of LEDs connected in series across the laterally spaced upper surface wiring and spacedly mounted along the printed circuit board; a high frequency electronic driver mounted in the shell and connected in series with the LEDs; voltage limiting devices mounted across the laterally spaced bottom surface wiring of the printed circuit board and in parallel with the LEDs; a lens bonded to the shell covering the printed circuit board for directing and delivering light from the LEDs, the shell and lens forming a tube for enclosing the LED bearing printed circuit board; the tube so formed having sealed ends to form a watertight fixture; and, input wires extending from the high frequency electronic dri

Abstract: A tubular LED lighting fixture comprises: a heat sink shell; a printed circuit board supported on the shell and having an upper surface and a bottom surface, longitudinally extending laterally spaced wiring on the upper and bottom surfaces, and, transverse heat pipes running through the printed circuit board; a plurality of LEDs connected in series across the laterally spaced upper surface wiring and spacedly mounted along the printed circuit board; a high frequency electronic driver mounted in the shell and connected in series with the LEDs; voltage limiting devices mounted across the laterally spaced bottom surface wiring of the printed circuit board and in parallel with the LEDs; a lens bonded to the shell covering the printed circuit board for directing and delivering light from the LEDs, the shell and lens forming a tube for enclosing the LED bearing printed circuit board; the tube so formed having sealed ends to form a watertight fixture; and, input wires extending from the high frequency electronic dri

Abstract: According to a method for supplying a plurality of cascade connected light sources including, a control signal (k) is sent to a supply apparatus (AA). The control signal corresponds to a desired value of light radiation intensity to be emitted by at least a part of said the light sources, An electric current (z) with variable frequency is supplied to the plurality of light sources (SL1, SL2 , . . . , SLn) so that the lamps (L) of each light source are crossed by the values of current (h) depending on the frequency values of the current (z) supplied to the plurality of light sources. A connection exists between the values assumed by the control signal (k) and the values of the current (h) circulating in the lamps (L) of the light sources (SL1, SL2, . . . , SLn).

Abstract: A light emitting unit includes a power supply line that supplies a power supply voltage to a light source part and a ground member that grounds the light source part, and the power supply line is disposed on a different layer from that of the ground member. The light emitting unit of the present invention may be included in a backlight assembly which may be included in a display assembly.

Abstract: Apparatus compensating for gain variations versus frequency of a traveling wave tube (TWT) is disclosed. The apparatus provides an RF interaction circuit section designed with specified mismatches causing internal reflections of the RF waves, such that the overall gain response is flattened out or inverted.

Abstract: A satellite is formed with a signal translation and amplification system which includes at least one communication path. Each communication path includes a plurality of radiation-cooled TWTs powered by a single EPC. Also included in the communication path is a high efficiency radiation panel capable of transmitting heat generated by said TWTs and EPC into space; as well as a radiating collector which is directly applied to each TWT, and is capable of transmitting heat generated by said TWT into space.

Abstract: Multiple gain stages are provided in a single traveling wave tube amplifier (TWTA). Each gain stage comprises an interaction circuit, an associated RF input, and an associated RF output. The gain stages are separated by a drift length that is selected to achieve a desired interaction between gain stages. In one embodiment that uses only one TWT, couplers, and adjustment blocks external to the TWT, feed-forward and feedback connections remove intermodulation distortion introduced by the TWTA.

Abstract: A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity (C4) portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation.

Abstract: A helix travelling-wave tube of the present invention includes a helix wave delay circuit having velocity tapers for improving a beam efficiency and reducing backward wave oscillation. The tube allows a small signal and a large signal synchronous voltage to coincide or be extremely close to each other and thereby allows its circuit to have a minimum length. The tube is therefore small size and light weight and involves a minimum of gain variation against voltage variation.

Abstract: A satellite is formed with a signal translation and amplification system which includes at least one communication path. Each communication path includes a plurality of radiation-cooled TWTs powered by a single EPC. Also included in the communication path is a high efficiency radiation panel capable of transmitting heat generated by said TWTs and EPC into space; as well as a radiating collector which is directly applied to each TWT, and is capable of transmitting heat generated by said TWT into space.

Abstract: Multiple radio frequency (RF) outlet ports are provided along the side of a slow wave tube to establish a distributed RF output in response to the transmission of an e.sup.- beam through the tube. The tube has a periodically rippled inner surface, and the outlet ports are spaced along the tube by substantially integral numbers of ripple periods. When implemented as a backward wave oscillator, RF power is extracted during a single pass through the tube; a travelling wave tube amplifier implementation is also possible. The separation of the RF extraction from the absorption of the e.sup.- beam at the end of the tube eliminates RF reflections and permits water cooling of the e.sup.- beam absorber. The RF extraction ports are also preferably configured as built-in mode converters from a TM.sub.01 cylindrical tube mode to a TE.sub.10 rectangular extraction mode, with four symmetrically arranged rectangular extraction waveguides at each extraction location combining their energies into a single TE.sub.10 output.

Abstract: The present invention is an anisotropically loaded helix assembly for use in a traveling-wave tube, and the corresponding method for making the same. The present invention includes a helix circuit concentrically supported within a conductive cylindrical housing by a plurality of dielectric support members. The present invention effects an improved efficiency and bandwidth in the performance of TWT by the material used to form the dielectric support members, the shape of the dielectric support members and the manner by which the anisotropic load is affixed to the dielectric support members.

Abstract: A crossed-field amplifier tube is constructed in which there is substantially no direct RF coupling between the output of the slow-wave structure on the anode and the input of the slow-wave structure of the cathode to thereby obtain a cathode-driven tube which is capable of RF pulsed operation into a linear accelerator cavity which presents a mismatched load, a short circuit impedance, at initiation and termination of the RF pulse without breaking into oscillation. During the RF pulse, the tube operates into a substantially matched load and provides high peak and average power.

Abstract: A traveling wave tube (10) includes a coupled cavity type slow wave structure (100) having a driver stage (52) and an output section (101) with a primary section (64) and a velocity taper section (82) which in combinattion produce maximum signal gain at a predetermined frequency. A gain flattening section (104) is preferably disposed between the driver stage (52) and the primary section (64) of the output section (101), and is designed to operate at a reduced phase velocity selected to produce minimum or negative signal gain at approximately the predetermined frequency. The gain characteristics of the driver stage (52), gain flattening section (104), primary section (64), and velocity taper section (82) combine to produce minimum signal gain variation over an operating frequency range which spans the predetermined frequency, and expand the bandwidth of the traveling wave tube (10).

Abstract: Two or more signal interaction structures (16,18), which may be klystron or traveling wave structures (32,50), are axially disposed in series between an electron gun (12) and a collector (14) for selectively velocity modulating an electron beam (20) generated by the gun (12) with a microwave input signal (IN1,IN2) and extracting a resulting amplified microwave output signal (OUT1,OUT2) from the beam (20). The interaction structures (16,18) are designed to operate in different frequency bands, for example the X and Ku bands, with only one of the structures (16,18) having an input signal (IN1,IN2) applied thereto at any given time. The interaction structures (16,18) are further designed such that the structures (16,18) which are not being used do not affect the structure (16,18) which is being used.

Abstract: An element with periodic structure for guiding electromagnetic waves propagating along a longitudinal axis of the structure at a speed below the velocity of light is disclosed. The structure includes a series of metal polar expansions aligned with the mentioned axis and forming a plurality of resonant metal cavities. The polar expansions have respective apertures aligned with each other so as to form a freeway for electron flow. First and second conductors are provided for cooperating with the polar expansions. The polar expansions each further respectively have first and second apertures for receiving first and second conductors that are preferably positioned diametrically opposed to each other with respect to the mentioned longitudinal axis.

Abstract: A traveling-wave deflection system comprising a pair of deflectors disposed opposite each other across the path of an electron beam from an electron gun to a screen in a cathode-ray tube. Each deflector has a helical conductor wound around a core structure generally extending along the beam path. If made solely of an insulating material as in the prior art, the core structures would be electrified in use of the CRT, with the consequent deflection defocusing and bright line displacement. Therefore, in order to avoid electrification, the core structures are each enveloped in an antielectrification layer of a conducting material having a higher resistivity than the helical conductor. An embodiment is also disclosed wherein the core structures are wholly of conductive material.

Abstract: A method is disclosed of employing free electron lasing action at a first frequency to achieve gain in output power at a second frequency. In a broadest sense, an electron beam is driven with an electromagnetic wave at said first frequency in a first stage, having a first spatial period, to cause bunching of the electron beam. The electrons in the beam are oscillated with a second stage, having a second spatial period, to generate electromagnetic wave power from said beam at the second frequency.In a specific embodiment, the second frequency is near a harmonic of said first frequency. And in a particular implementation, the first stage is provided by a free electron laser having a first wiggler with a first spatial period, the second stage is a second wiggler having a second spatial period and a drift region is disposed between the first and second stages.

Abstract: A travelling-wave tube has a cylindrical sleeve containing a delay line and a coupling device between the delay line and an external microwave circuit for removal or injection of microwave energy. This external circuit comprises a transmission line possessing a conductive internal core. A conductive part is placed at one end of the delay line. It has a coupling pin that projects inwards into the sleeve and is brazed to an end of the delay line. The conductive part is brazed to the sleeve. The coupling between the delay line and the external circuit is made between the part and the internal conductive core of the transmission line. This coupling is without contact, a narrow gap being prepared between the external surface of the part located on the side of the coupling pin and the internal conductive core.

Abstract: A coaxial TWT comprises a hollow beam gun which injects a thin annular beam between multifilar helices independently supported by thin-walled dielectric sleeves. The beam is focussed by a balanced, coaxial PPM focussing assembly, causing a stable hollow beam flow. The input and output coupling helixes, and the interaction helices which form the slow-wave structure on the exterior and the interior of the hollow beam, respectively, are preferably counterwound with respect to each other to provide greater frequency bandwidth than when similarly wound. Input and output helix coupling to either the inner or the outer helix is possible.

Abstract: A coupled-cavity linear accelerator for accelerating charged particles to velocities greater than about one-third the speed of light. The accelerator includes a first tank for accelerating charged particles at a first velocity to a second velocity and a second tank for accelerating the particles to a higher third velocity. A bridge coupler for focusing a beam formed by the charged particles joins the first and second tanks. Each tank is substantially symmetrical about an axis and includes a generally cylindrical tank outer wall having an inner surface and an outer surface. A series of axially spaced disks are positioned inside the tank and bear on the inside tank surface. Each disk has an outer diameter greater than the as-manufactured inside diameter of the tank wall so that each disk causes an annular indentation in the inner surface of the outer wall. At least one washer is supported by each of alternating disks.

Abstract: A slow-wave circuit for a TWT has periodic transverse plates extending across the axial by extending vacuum envelope. An opposed pair of apertures 24, 26 in each plate 20 couple adjacent cavities 28 between plates 20. Coupling apertures 24 in alternate plates 20 are rotated transverse to apertures 26 in the other plates to provide coupling only between adjacent cavities 28. Each plate 20 has transverse ridges 30 enclosing its axial beam aperture 22. The ridges 30 are orthogonal to the coupling apertures 24, 26 to increase beam coupling and decrease capacitance for wider bandwidth and higher impedance.

Abstract: A traveling-wave tube has coupled cells in a periodic arrangement defined between apertured irises separated by respective spacers. The spacers have dielectric waveguides terminating in lossly loads to attenuate RF frequencies above the upper limit of the frequency to be amplified by the tube.

Abstract: A helix slow-wave circuit for use in a linear-beam microwave tube device, comprises a first helix formed by a first wire-like member wound in a first sense at a plurality of turns, and a second helix formed by a second wire-like member wound at a plurality of turns in a second sense opposite to the first sense so as to coaxially surround and superpose on the first helix so that the first and second helixes intersect each other at suitable intervals along an axial direction of the helixes. The first helix is fixed to the second helix in at least some of intersecting points between the first and second helixes.

Abstract: An orotron for generating near millimeter wavelength radiation at a selectable output frequency within a wide frequency range, in which the orotron output power is automatically tuned electronically at the selected output frequency. A piezoelectric electromechanical positioning device is connected between the two mirrors forming the open resonator of the orotron to determine the mirror separation in accordance with a position control signal. The electron beam acceleration voltage, which determines the orotron output frequency, and the position control signal are adjusted simultaneously so as to tune the output power at a single oscillation mode of the orotron resonator over a wide frequency range. In the preferred embodiment, the actual output frequency is detected and compared with the selected output frequency, and the beam acceleration voltage and mirror separation simultaneously adjusted to continuously tune and maintain the orotron output at the selected frequency.

Abstract: A traveling wave type amplifier. The device features a pair of short helical input and output couplers through which an electron beam is projected. Application of an RF signal to the couplers serves to modulate the electron beam. A drift tube to be positioned between the couplers is dimensioned to attenuate the RF signal while permitting the modulated electron beam to pass through. An amplified output signal is extracted from the output helix. Gain of the tube is enhanced by a linearly decreasing magnetic focussing field.

Abstract: Microwave oscillators and amplifiers which utilize a superconducting slow-wave circuit. The slow circuit is made from materials which exhibit superconductivity at relatively high critical temperatures. The slow wave circuit is integral with the device's vacuum housing. Coolant exterior to the vacuum housing maintains the circuit in the superconducting state. The slow-wave circuit, which protrudes into the vacuum housing provides modulation of an electron beam which traverses the interior of the vacuum housing. Output power is ultimately extracted from the slow wave circuit.

Abstract: A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.

Abstract: A crossed-field amplifier has a cathode in the form of a P-N junction semiconductor which is biased to the conductive state to cause the crossed-field amplifier to amplify. The P and N regions of the semiconductor are connected to an energy source which is pulsed to produce conduction in the P-N junction and thereby allow secondary emission from the cathode. A reverse bias voltage prevents secondary emission from the cathode. The tube requires only low voltages to be applied to the cathode P-N junction to completely deactivate the crossed-field amplifier tube without requiring the removal of the RF drive pulse applied to the cathode- or anode-slow-wave circuit and without requiring the removal of the DC high voltage power supply which therefore need not be pulsed.

Abstract: A high-power switch tube is shown constructed from a plurality of electron guns each gun having a cathode and an anode. Between the cathode and anode is mounted a shadow grid closest to the cathode beyond which is mounted a control grid, a screen grid, and, in some applications, by a suppressor grid. Each anode is formed with an anode cavity having an opening that is smaller in dimension than the largest dimension of the cavity thus forming a Faraday cage collector which prevents secondary emission problems.

Abstract: In an accelerator for accelerating charged particles by using electro-magnetic wave, in which a plurality of cells are disposed periodically, a washer-shaped electrode separated from the cylinder wall is located at the boundary of each of the cells, which electrode has a hole, through which accelerated charged particles pass, at its center portion and an approximately uniform thickness. The thickness and the diameter of said washer-shaped electrode and the gap between said washer-shaped electrode and the inner surface of said cylinder are so chosen that the average strength of the accelerating electric field is highest. The peak strengths of the electric field are approximately equal at the outer and inner peripheral portions of said washer-shaped electrode.

Abstract: A coupled cavity travelling wave tube of the space harmonic type is provided wherein the interaction gaps in successive cavities are alternately offset towards the input end of the slow wave structure and towards the output of the slow wave structure, whereby beam electrons which are synchronous at band edge frequencies tend to experience a phase reversal in the electro-magnetic wave propagating in the slow wave structure, at each successive interaction gap.

Abstract: A traveling wave tube made in accordance with this invention wherein the folded waveguide interaction circuit and the input/output transitions to standard waveguides are made of a single piece of metal such as oxygen-free, high conductivity copper. By manufacturing the folded waveguide circuit and the input/output circuit-to-standard waveguide transition out of one piece of material, VSWR on the order of 1.1:1 is expected for traveling wave tubes intended to operate at 94 GHz. Furthermore, this invention minimizes expensive tooling and labor while providing a higher yield of traveling wave tubes.

Abstract: A travelling wave tube comprising a tube and a helix mounted in the tube, the helix being made of diamond and being coated at least partially with an electrically conductive material.

Abstract: A travelling-wave tube comprising a delay line in the form of a helix line which is disposed inside of a solid metal vacuum envelope. A high-performance travelling-wave tube whose delay line is distinguished by very good dissipation of the stray heat. A large bandwidth results by providing the delay line with a core of insulator material which has a metal layer at its inside and outside generated surfaces.

Abstract: A device for converting the kinetic energy of an intense relativistic electron beam (IREB) into trains of multi-gigawatt AC electrical pulses comprising a foilless diode for generating an IREB and injecting the IREB into one end of a drift tube. The device further includes a modulating circuit for modulating the IREB current while in the drift tube to obtain longitudinally spaced bunches of electrons, and a coaxial transmission line with the end of its center conductor disposed across the other end of the drift tube in the path of the IREB. A gap is disposed between the end of the drift tube and the end of the center conductor. The modulated IREB induces a voltage in the coaxial transmission line. This voltage appears across the gap to slow down the electrons and to convert the kinetic energy of the IREB into electrical energy that propagates along the coaxial transmission line.