1,055,735. Magnetic amplifiers. NIHONGENSHIRYOKU KENKYU SHO. Jan. 2. 1964 [Jan. 8, 1963], No. 147/64. Heading H3B, In a magnetic amplifier having a negative feedback winding the number of turns of this winding are determined by the equation α<SP>1</SP>Nf=¢ where α<SP>1</SP> is the gain of the amplifier without feedback as shown in Fig. 5. This results in the output having the same value for equal positive or negative inputs to the control winding. Complete symmetry may be obtained by supplying a biasing current to the negative feedback winding.