Gte Automatic Electric Incorporated

Thomas J Barzen

Frederick J Kiko

A circuit for increasing the inductance of a transformer as used in a telephone line circuit. An operational amplifier with appropriate feedback is connected across a separate winding of the transformer to provide the reactive inductance. To compensate for changes in resistance of the winding, a field effect transistor is controlled by the same amplifier output to provide a positive resistance in the feedback path and thus maintain balance. An operational amplifier and diode are arranged to cooperate with the negative inductor to prevent lock-up.

Start-up circuit for negative inductance multiplier

A circuit for increasing the inductance of a transformer as used in a telephone line circuit. An operational amplifier with appropriate feedback is connected across a separate winding of the transformer to provide the reactive inductance. To compensate for changes in resistance of the winding, a field effect transistor is controlled by the same amplifier output to provide a positive resistance in the feedback path and thus maintain balance.

Growing community of inventors

Addison, IL, United States of America

Thomas J Barzen