Hall-effect analogue a.c. square-root computer

A fully transistorised analogue a.c. square-root computer based on the Hall effect is described. The output of the computer¿the Hall direct current¿is directly proportional to the square root of the amplitude of the input voltage vi. The proportionality is maintained to within 4% for the input-voltage dynamic range 0.2mV ¿vi¿ 50mV. The characteristics of the computer at 50Hz are presented.