Abstract: A position indicating device for providing a generally linear output in response to displacement; the system includes a Hall effect device and apparatus for providing a response therein in accordance to displacement of a movable stylus or plunger and the method of making the same.

Abstract: An alternator-battery electrical system test apparatus which, in one modification, includes a four stage voltage level sensing system, each stage being operative in response to a particular condition of the electrical system under test. The first stage senses the filtered and unfiltered output of the alternator to provide a pulsed output which provides an indication of any diode failure or winding failure in the alternator. The remaining three stages sense the voltage output from the alternator as compared to a fixed reference, each particular voltage condition providing an indication of a preselected electrical condition within the circuit. The entire system is calibrated by a single calibrating resistor.