基本信息
摘要：In an angle digitizer of the type in which a gate 23 is opened at a time determined by a reference signal and closed by a signal the time of which is dependent on the unknown angle, clock pulses being counted during the time interval between these signals, signals representing sin # and cos #, where # is for example either the angle through which a shaft has rotated or the phase difference between two signals, are fed via semi-conductor switches 11, 12, receiving modulating signals in phase quadrature, a mixer 17, tuner 18 and squaring circuit 19 to a differentiating amplifier 20 the output pulses from which control the closing of the gate 23. The gate is opened, after an interrogate signal 27 has enabled a switch 22 and reset counter 25, by the next reference signal which is derived from one of the modulating signals. The count may be fed to an indicator or computor.
摘要附图：
