| 摘要 |
In an altimeter having a commutator disc attached to the output shaft of the aneroid, an encoder for supplying a digital analyzer with an operational signal upon a change in altitude. Opaque and translucent segments are concentrically located at various radii on the commutator disc. A series of light emitting diodes are located at the various radii to present illumination to the opaque and translucent segments. A corresponding series of photosensitive transistors are located in line with the light emitting diodes. Each of the photosensitive transistors upon receiving illumination from the light emitting diodes will produce an electrical current signal. The electrical current signal from each photosensitive transistor is carried to the base of a switchingtransistor where a voltage level translation is carried out to produce a series of operational signals representative of a code on the commutator disc associated with a particular altitude which are compatible with the digital analyzer. The operational signals are transmitted to the digital analyzer for retention in a memory of an aircraft air traffic control transponder until said transponder is interrogated, at which time said operational signals are recorded and transmitted to the air traffic control ground station. When the aircraft altitude is changing, each new altitude increment to the transponder destroys the previous altitude input such that only the most recent data is stored in the transponder memory. An inhibitor, connected to thepower supply of the photosensitive transistors and the digital analyzer, in response to a command signal will interrupt the creation of the operational signal and allow information, other than altitude, to be retrieved from the memory without interference. |
