Negative resistance compensated transformer

摘要

A compensated circuit for use in interfacing a transmission device to a cable facility. The circuit includes a transformer one winding of which is connected to the cable facility and the other winding of which is connected through an impedance generating device to the transmission device. The circuit provides a predetermined one of a number of selectable impedances to the cable facility. The impedance generating device allows the desired impedance to be elected and includes a negative resistance generating circuit which responds to the current flowing in the loop formed by the winding and the impedance generating device.