AC voltage video signal level measurer - has circuit adding output signals of amplifier and supplying a=d converter assigned to evaluator for control e.g. register

摘要

The input signal (E) to be measured is supplied to a measuring unit e.g. an a-d converter via an amplifying circuit. The degree of amplification is adjusted so that the input to the a-d converter is held constant at a specified level. The amplifying circuit consists of several individual amplifiers (V1-V4) of differing amplification factors. The outputs of the amplifiers are connectable together in any combination in an adding circuit (A) connected to the ADC via controlled switches (S1-S4). An amplified signal can be supplied from one or any number of these amplifiers. The levels of amplification (v) of the parallel connected amplifiers are measured according to the equation v = 2 to the power of (n-1), where n is the number of amplifiers and the associated switches are controlled via a circuit (R), the control output of which corresponds directly to the binary value of the desired amplification. ADVANTAGE - Measuring system can be built cost effectively.