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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discrete component (electrical components). A device such as an individual resistor or capacitor. Discrete components have been replaced in many modern circuits with integrated circuits in which a number of individual components are built into a single integrated circuit (IC) chip. discriminator (frequency modulated radio circuit). A circuit in a frequency modulated (FM) radio receiver that changes deviations in the frequency of the carrier into amplitude variations of the audio-frequency output. The audio-frequency output, used to operate a speaker, is a duplicate of the modulating signal in the transmitter. disengage. To disconnect, or release one device or component from another. dish antenna (radio equipment antenna). A shallow, concave, circular reflector used with a radio antenna, actually with the shape of a parabola. Signals from a transmitter are received in the dish and are reflected in such a way that they concentrate at a point from which they are picked up and carried into the receiver. Signals picked up by a dish are highly directional. disk area (helicopter parameter). The total area swept by the main rotor of a helicopter. disk brake. A popular type of nonservo brake used on aircraft. See multiple disk brake and single disk brake. disk loading (helicopter parameter). The ratio found by dividing the gross weight of a helicopter by the total area of its rotor disk. disk sander (power tool). A power tool consisting of a rotating disk covered with an abrasive material. The part to be sanded, or abraded, is held against the disk, and the abrasive wears it away. dispersant. A material or substance used to keep something dispersed, or suspended, in something else. Ashless Dispersant (AD) oil contains a dispersant that keeps all the contaminants picked up by the oil dispersed until it passes through filters where the contaminants are trapped. If the oil did not have the dispersant, the contaminants would settle out and plug passages inside the engine. displaced threshold. The beginning of the usable portion of a runway that is located at a point other than the designated beginning of the runway. display tube (electrical instruments). A cathode-ray tube used to display information. Cathode-ray oscilloscopes and computer video monitors use display tubes. dissimilar-metal corrosion. Corrosion that forms where two different types of metals are in contact with each other. The severity of the corrosion is determined by the relative location of the metals in the electrochemical series. See electrochemical series. dissipate. To scatter, or disperse. Smoke from a smokestack blown by the wind is dissipated, or scattered, into the atmosphere. dissipate (power). To use something up. When electrons flow through a resistor, power is dissipated, and the resistor gets hot. The resistor dissipates power by converting it into heat. dissolve. To become a liquid and form a mixture with another liquid. When grains of solid sugar are put into a glass of water, the sugar dissolves. It becomes a liquid and mixes with the water. |
