摘要:
A vacuum tube optimization circuit can automatically ensuring that the preheating required for the thermionic effect to occur within the vacuum tubes within a vacuum tube device, has been sufficient to allow the vacuum tubes to reach their operating temperatures, before allowing signal voltage or current to be applied to their anodes, cathodes, and/or other thermionically-active components. This reduces the diffusion of component-specific surface material coatings onto the surfaces of other internal elements within the vacuum tube, functioning to extend the service life of the vacuum tubes.
摘要:
A filament assembly for use in an x-ray emitting device or other filament-containing device is disclosed. In one embodiment, an x-ray tube is disclosed, including a vacuum enclosure that houses both an anode having a target surface, and a cathode positioned with respect to the anode. The cathode includes a filament assembly for emitting a beam of electrons during tube operation. The filament assembly comprises a heat sink and a plurality of filament segments. The filament segments are configured for simultaneous emission of an electron beam for impingement on the target surface of the anode, and are electrically connected in series. Each filament segment includes first and second end portions that are thermally connected to the heat sink, and a central portion that can be configured with a modified work function for preferential electron emission.
摘要:
A capacitively coupled plasma reactor comprising a processing chamber, a first electrode, a second electrode and a thermoelectric unit. The processing chamber has an upper portion with a gas inlet and a lower portion, and the upper portion is in fluid communication with the lower portion. The first electrode has a front side and a backside and is positioned at the upper portion of the processing chamber. The second electrode is positioned in the lower portion of the processing chamber and is spaced apart from the front side of the first electrode. The thermoelectric unit is positioned proximate to the backside of the first electrode and is capable of heating and cooling the first electrode.
摘要:
A klystron tube for amplifying signals at microwave radio frequencies utilizes an electron source for emitting electrons through a field focused by a high energy magnet in the RF section of the tube. After the electrons have passed through the active area of the tube, the electrons strike the collector which, in this case, is a multistage depressed collector. The multistages of the depressed collector are connected to high energy voltage sources of different potentials. The klystron tube with the multistage depressed collector is uniquely used here for the first time in a ground based satellite or terrestrial communications system.
摘要:
An electron emission device for attracting electrons emitted from an electron emission element to an anode, includes a current detector for detecting a flow-in current to said electron emission element and a flow-out current from the electron emission element. The difference between the flow-in current and the flow-out current is calculated and the voltage applied to the electron emission element is adjusted in accordance with the difference between the flow-in current and the flow-out cuttent.
摘要:
An apparatus for heating the cathode of an electronic power tube, having a supply for delivering a heating current to the cathode, an interrupter circuit for periodically interrupting the flow of heating current to the cathode, and controls for controlling the duration of these periodic interruptions and for regulating the net amount of heating current. To achieve this, the controls include a voltage control that varies in such a way so as to bring the heating current from a value of O to Io (where Io is the correct heating current at which the tube will be in a pre-heated condition) during a first, predetermined time period, and then from a current Io to a current Im (where Im is the optimum value for the heating current when the tube is normally operating), during a second predetermined time period.
摘要:
The power regulator includes a pass transistor connected between a first supply providing a first unregulated pulsating d.c. voltage and load whose resistance is initially low, but rises to a higher value as power is supplied thereto. An amplifying transistor controls the current flow through the pass transistor and load. A zener diode limits the amplitude of the load voltage. A second supply provides a control voltage to the amplifying transistor which regulates the output power by shaping the output voltage waveform. A starting circuit, connected between a power supply, the load and the amplifying transistor, initially supplies starting current for the regulator. The starting circuit is turned off by the increasing voltage developed across the load as power is delivered thereto.