Tester for a copier

摘要

A tester can resolve a sensed signal whose duty cycle is proportional to the amount of a developer disposed in a copier. The tester includes an input device and an indication device. The input device is coupled to the copier for providing a processed signal relating to the extent the sensed signal resides in a predetermined state. The indication device is coupled to the input device and can provide an indication of the magnitude of the processed signal.