Magnetic amplifier performs analytical operations

THE CIRCUIT shown contains two saturable reactors with “square loop” cores. An alternating voltage is applied to their windings through rectifying diodes. During positive half-cycles of the supply voltage V
c
the core flux of the converter stage rises from some preset value to saturation. Before “firing” only a small magnetizing current flows; after firing the supply voltage appears across the load resistance R
c
and the winding resistance r
c
. The preset flux is determined jointly by the line voltage, which in negative (presetting) half-cycles tries to remove the core from positive saturation and by the opposing voltage of a given half-wave sinusoidal signal V
s1
1 This stage converts the waveform of the signal V
s1
into a net output waveform V
c
′ of nearly equal half-cyclic area.