The World's Largest Public Domain Media Search Engine
Bell telephone magazine (1922) (14569847558)

Similar

Bell telephone magazine (1922) (14569847558)

description

Summary


Identifier: belltelephonemag09amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive



Text Appearing Before Image:
fall back, and then closed the circuit through heavycalling battery B-l, operating tap bell R-D. The operatorthen shifted plug P-d from the right-hand to the left-hand hole,disconnecting subscriber Z)s central office burglar alarm circuitand connecting the operators telephone, T, to subscriber Z)sline. When his bell rang, subscriber D moved his substationswitch from the right-hand to the left-hand contact, thus dis-connecting his substation burglar alarm circuit from his lineand connecting in his telephone, T-D. The operator, after notifying subscriber D that subscriber Bwished to talk with him, removed plug P-d from the left-handhole, moved switch 5 to its right-hand contact, and insertedplug Q, at the end of cord C, in hole H-d. This placed thetelephones of subscriber B, the operator and subscriber D all inone circuit (Fig. 4). The operator could thus determine, bylistening in, when the conversation was finished. When thisoccurred, the operator withdrew plug Q from hole H-d, re- 209
Text Appearing After Image:
210 THE FIRST TELEPHONE SWITCHBOARD placed plugs P-b and P-d in the right-hand holes of the centraloffice plug and block switches, and moved switch 5 to its left-hand contact. When subscribers B and D had moved theirsubstation switches to the right-hand contacts, the operatorrestored the shutters of annunciators A-b and A-d (the latterhaving fallen when its galvanometer circuit was opened), andclosed switch W. The apparatus at the central office and sub-stations was then in readiness for another call to be made. G. K. Thompson,R. B. Hill. Note: The authors wish to express their indebtedness to Mr.W. L. Richards, Consulting Historian of the Bell TelephoneLaboratories, for his assistance in the preparation of this arti-cle. 211 Worlds Telephone Statistics January 1, 1929 ACCORDING to the latest annual survey of the worldstelephones which was recently completed by the ChiefStatisticians Division of the American Telephone and Tele-graph Company, there were 32,712,284 telephones in the wor

date_range

Date

1922
create

Source

Prelinger Library
copyright

Copyright info

public domain

Explore more

bell telephone magazine 1930
bell telephone magazine 1930
picryl logo

The World's Largest Public Domain Media Search Engine

PICRYL is the largest media source for public domain images, scans, and documents. PICRYL is an AI-driven search & similarity engine. PICRYL makes the world's public domain media fun to find and easy to use.

Get Archive LLC, creator of PICRYL, endeavors to provide information that it possesses on the copyright status of the content and to identify any other terms and conditions that may apply to the use of the content, however, Get Archive LLC offers no guarantee or assurance that all pertinent information is provided, or that the information is correct in each circumstance.

Permission for use, re-use, or additional use of the content is not required. GetArchive believes there are no usage restrictions or limitations put on content in the U.S. Get Archive LLC does not charge permission and license fees for use of any of the content on PICRYL, however, upon request, GetArchive can provide rights clearance for content for a fee.

Get Archive LLC is the owner of the compilation of content that is posted on the PICRYL website and applications, which consists of text, images, audio, video, databases, tags, design, codes, and software ("Content"). However, Get Archive LLC does not own each component of the compilation displayed and accessible on the PICRYL website and applications. If you have specific questions or information about content, the website, and applications, please contact us.

Developed by GetArchive, 2015-2024