Induction Coil 2-3
Operating the handset switch closes the circuit consisting of the switch, battery, transmitter, and 2-3 section of the induction coil. Since this circuit has a relatively low impedance, large current changes are produced by the transmitter when it is activated by speaking into the transmitter. These current changes induce relatively high voltages in the entire 1-4 winding of the induction coil and across terminals L1 and L2 to which the line is connected.
induction coil. The induction coil (Coil C-105) is an autotrans- former with one continuous winding tapped at terminals 2 and 3 so as to form the 1-2 section, the 2-3 section, and the 3-4 section. ( See figs. 25 and 26.)