时间：2011-03-11 23:13来源：蓝天飞行翻译 作者：admin 点击：次
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High-frequency signals can feed back from one electrode to another through the interelectrode capacitance inside a tube. To prevent this feedback, neutralizing circuits must be used. interelement capacitance. The capacitance inside a bipolar transistor caused by the junction between the P-material and the N-material. interference angle (poppet valve dimension). The difference between the angles at which the valve seat and the valve face are ground. Normally the valve seats are ground with between 0.5° and 1° greater angle than the valve face. This allows the face to touch the seat with a line contact that provides the best sealing. interference drag (aerodynamic drag). Parasite drag caused by air flowing over one portion of the airframe interfering with the smooth flow of air over another portion. interference fit. A type of fit used when assembling certain mechanical devices. To create an interference fit, a hole is made smaller than the part that fits into it. The material containing the hole is heated to expand the hole, and the object to fit in the hole is chilled to shrink it. The parts are easily assembled when one is hot and the other is cold, but when they reach the same temperature, the fit is so tight they will not loosen in service. intergranular corrosion. A type of corrosion which forms along the boundaries of the grains inside a piece of metal alloy. Stress corrosion and exfoliation corrosion are types of inter-granular corrosion. interlock. A form of automatic safety control. An interlock in a device can prevent an action from occurring until the device is ready for the action. An interlock can be installed on the door of a compartment so the door cannot be opened when the equipment inside the compartment is operating. When the door is opened, the interlock switch automatically turns the power off and discharges any high-voltage capacitors inside the housing. intermediate fix (air traffic control). The fix that identifies the beginning of the intermediate approach segment of an instrument approach procedure. intermediate frequency (radio receiver). A single frequency of alternating current produced inside a superheterodyne radio receiver. A superheterodyne receiver circuit is efficient because most of its amplification is done with a single intermediate frequency, rather than with a wide band of frequencies. A local oscillator inside the receiver produces an alternating current whose frequency is always a constant amount different from the radio-frequency signal being received. When the local oscillator signal is mixed with the received signal, two other frequencies are produced: One frequency is the sum of the two, and the other is the difference between the two. Filters allow only the signal whose frequency is the difference between the two to be amplified. This is the intermediate frequency, the IF. intermediate frequency transformer (radio receiver component). An interstage coupling transformer used in a superheterodyne radio receiver. Both the primary and secondary windings of the IF transformer are tuned to the intermediate frequency. See intermediate frequency. |
