Abstract: A circuit which performs loop supervision, transmit, receive, and transmit and receive regulation and sidetone balance. A loading circuit shunts excess current from the transmit and receive circuits under short loop conditions. The loading circuit also controls regulation of the transmit and receive circuits. Use of constant current power supplies external to the transmit and receive circuits prevents modulation of the power supplies.
Type:
Grant
Filed:
June 15, 1981
Date of Patent:
August 23, 1983
Assignees:
GTE Automatic Electric Labs Inc., GTE Labs Inc.
Inventors:
William Stobbs, Charles Hines, Rickey W. Light