Closed loop Hall effect sensors have zero circuit insertion loss. Laboratory Tests Fig. 1, on page 44, illustrates the test lab setup. An ac drive is driving a 600 Hp dyne set.

Figure 3 Finding the loop gain T of the circuit of Figure 1 via Rosenstark’s technique: Terminating the return side (a ) on an open circuit to find Toc , and (b ) on a short circuit to find Tsc .