Deviation detector for AC signal - has switching circuit delivering signal when DC component is at either max. or min.

摘要

The detector senses any deviation of an a.c. signal from a specified characteristic. The a.c. signal is applied to a circuit that delivers a signal when the d.c. component is at either a max. or min. This signal is completely outside a stationary signal area during a specified min. period, or when the a.c. component is at a min. and the peak-to-peak signal amplitude falls below a specified min. value during a specified min. period. Once a signal is delivered it can be suppressed only on reception of an erasing signal. The switching circuit can comprise an a.c./d.c. signal AND gate (3) with two inputs (1, 5). An a.c./d.c. converter (7) follows the gate (3) and has its output connected to the d.c. input (5) of the AND gate (3).