GB901946A - Improvements in and relating to internal loudspeaker communication systems - Google Patents

Improvements in and relating to internal loudspeaker communication systems

Info

Publication number
GB901946A
GB901946A GB2533159A GB2533159A GB901946A GB 901946 A GB901946 A GB 901946A GB 2533159 A GB2533159 A GB 2533159A GB 2533159 A GB2533159 A GB 2533159A GB 901946 A GB901946 A GB 901946A
Authority
GB
United Kingdom
Prior art keywords
interconnection system
relating
communication systems
pick
master station
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB2533159A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to GB2533159A priority Critical patent/GB901946A/en
Priority to FR833714A priority patent/FR1266732A/en
Publication of GB901946A publication Critical patent/GB901946A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/001—Two-way communication systems between a limited number of parties
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/04—Arrangements for interconnection not involving centralised switching involving a separate line for each pair of parties

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Emergency Alarm Devices (AREA)

Abstract

901,946. Sub-station equipment. BARON, O. June 30, 1960 [July 23, 1959], No. 25331/59. Drawings to Specification. Class 40 (4). A private interconnection system using loudspeakers is coupled to speech from the instrument of a public system by means of an inductive pick-up the output of which is amplified and is connectible to one or more loud-speakers of the interconnection system from a master station. The interconnection system is the same as that described in Specification 843,809. The master station can communicate with one or more stations over a transmit/receive transistor amplifier. The inductive pick-up is secured to the public telephone instrument by means of a suction pad and picks up signals from the line transformer. Switches to connect power to the amplifier and a warning light are operated by a control knob which also controls an attenuator in shunt across the pick-up.
GB2533159A 1959-07-23 1959-07-23 Improvements in and relating to internal loudspeaker communication systems Expired GB901946A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB2533159A GB901946A (en) 1959-07-23 1959-07-23 Improvements in and relating to internal loudspeaker communication systems
FR833714A FR1266732A (en) 1959-07-23 1960-07-22 Improvement of indoor telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2533159A GB901946A (en) 1959-07-23 1959-07-23 Improvements in and relating to internal loudspeaker communication systems

Publications (1)

Publication Number Publication Date
GB901946A true GB901946A (en) 1962-07-25

Family

ID=10225950

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2533159A Expired GB901946A (en) 1959-07-23 1959-07-23 Improvements in and relating to internal loudspeaker communication systems

Country Status (1)

Country Link
GB (1) GB901946A (en)

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