Installation téléphonique à lignes partagées.

摘要

628,200. Switch covers. WESTERN ELECTRIC CO., Inc. Aug. 7, 1947, No. 21769. Convention date, July 11, 1940. Drawings to Specification. [Class 38(v)] [Also in Group XXXIX] The removal of the dust cover of a twoposition polarized relay which selects one of two metering circuits in a telephone system (see Group XXXIX) opens auxiliary contact springs included in both circuits in order to permit adjustment without danger of false operation.