Telephone -- Private branch exchanges
Subject
Subject Source: Library of Congress Subject Headings
Found in 1 Collection or Record:
United States Coast Guard Station Telephone Line Records
Collection — Box 1
Identifier: MS-821
Abstract
Records, 1940-1978, of telephone lines for three United States Coast Guard stations in Lake Superior, Michigan: Huron Island, Eagle Harbor, and Portage Entry. Records include location diagrams of poles in relation to surrounding structures, span of cables, kind of material and date set. Also includes Bell System Practices manuals, by AT and T, for private branch exchange installation and maintenance.
Dates:
1940-1978