| 摘要 |
An apparatus for remotely monitoring the position of a rotatable member as the rotatable member is rotated about an axis of rotation by an axle, the apparatus including a substrate on which an electrode array is disposed and on one surface of the electrode array is a plurality of spacedapart, excitable electrodes defining a center portion, an aperture in the substrate located in the center portion for receiving the axle, a center electrode connected to a receiver circuit at least partially circumscribing the aperture, a guard composed of a conductive strip, both the guard and the center electrode disposed in the center portion on the same surface of the substrate. The center electrode is connected to the receiver circuit which senses current amplitude flowing from capacitors formed by a meter hand attached to the rotatable member, the center electrode and the excitable electrode. The receiver circuit is composed of a JFET amplifier, a multiplexer an asynchronous rejection circuit, a low-pass filter, analog to digital converter and an oscillator.
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