Toner concentration monitor

摘要: A toner concentration monitor senses changes in the effective dielectric constant of a developer mixture whose with variations mixture. The is type having capacitive probe immersible such that capacitance value said varies Means are provided for creating an electrical pulse train signal predetermined frequency and variable width. width adjusted response to probe. pulses created by multivibrator circuit which turned on clock has time determined Each first portion fixed duration second may be attenuating relative so as increase percent total attributable portion.