时间：2011-03-11 23:18来源：蓝天飞行翻译 作者：航空 点击：次
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The pilot may temporarily level off at any intermediate altitude. However, once an altitude has been vacated, he may not return to that altitude. Pilot’s Operating Handbook. See POH. pilot weather report (air traffic control). A report of meteorological phenomena encountered by aircraft in flight. pinch-off voltage (FET specification). The amount of reverse voltage required on the gate of a field effect transistor to decrease the source-to-drain current to some specified low value. pin contacts (electrical connectors). Contacts in one half of an electrical connector, made in the form of metal pins. These pins, called male contacts, fit into sockets, female contacts, in the other half of the connector. Pin contacts are normally used on the half of the connector in the “cold” part of the circuit, the part not connected to the source of power. PIN diode (semiconductor device). A semiconductor diode having a layer of P-silicon and a layer of N-silicon. Between these two layers is a thin layer of undoped silicon called intrinsic silicon. PIN diodes are used in high-frequency switching circuits because of their ability to turn on and off at an extremely fast rate. pinhole (finishing system). A small hole in the film of aircraft finishing material left by a bubble. The bubble migrated to the surface of the material and burst after the material had dried too much to flow into the resulting hole. pinion. A small gear that meshes with a larger gear, a sector of a gear, or a toothed rack. pin jack (electrical connector). A single female connector that accepts and holds a small metal pin attached to the end of a wire or a test lead. Pin jacks are used on test equipment to attach test leads to the instrument. pinked-edge fabric (aircraft fabric). Aircraft fabric having a series of small V-cuts along its edge made by cutting the fabric with pinking shears. Pinked-edge fabric does not ravel. pinked-edge tape. Cloth tape whose edges have small V-shaped notches cut along their length. The pinked edges prevent the tape from raveling. pinking shears. Special fabric-cutting scissors that produce a series of small V-shaped notches where the fabric is cut. These notches keep the edges of the fabric from raveling. pin knot cluster. A group of knots, all having a diameter of less than approximately 1/16 inch. pinouts (electronic circuit diagram). Identification of each of the external connections of an integrated circuit chip. pin punch. A long punch with straight sides. A pin punch can be passed through bolt holes in a piece of equipment to temporarily hold its pieces together until they can be bolted. A pin punch can also be used to drive bolts, rivets, or pins from tight-fitting holes. pin spanner. A special type of wrench used to turn ring-shaped nuts. Thin, ring-shaped nuts are used on cylinders and rods as mechanical stops and locking nuts. These nuts are turned with a pin spanner whose pins fit into small holes in the outer circumference of the nut. |
