At&t Bell Laboratories

Bell Telephone Laboratories

James D McElroy

James N Giacopelli

Thomas M Taylor

William B Grupen

Howard M Cohen

Lloyd Berrin

A stored program energy control system operates with the control of a telephone communications system to improve its energy efficiency by removing power from station sets and their associated visual indicators when they are inactive. Inactive station sets are identified by establishing minimal intervals of nonuse to define the inactive status. The energy control system responds to events like incoming calls and switchhook activity to restore power to the station set. Since energy is applied to a station set only when precisely needed, the overall energy drain of the system is greatly reduced.

Stored program power control system for improving energy efficiency for

A method of fabricating thin and thick film resistors which results in stable resistance characteristics, ability to withstand high current or voltage and a precise method of trimming small resistors. After the resistor film (20) and contacts (22 and 23) thereto are formed, the resistors are trimmed by a cut (24) along the length dimension so that the width of the current path is reduced uniformly. The waste portion of the resistor is then separated from the circuit by a cut (27) along its width. Current crowding in the vicinity of the cut is therefore essentially eliminated.

Fabrication of film resistor circuits

Growing community of inventors

Allentown, PA, United States of America

James D McElroy