GB702571A - Improvements in or relating to loudspeaking telephone installations - Google Patents

Improvements in or relating to loudspeaking telephone installations

Info

Publication number
GB702571A
GB702571A GB25506/51A GB2550651A GB702571A GB 702571 A GB702571 A GB 702571A GB 25506/51 A GB25506/51 A GB 25506/51A GB 2550651 A GB2550651 A GB 2550651A GB 702571 A GB702571 A GB 702571A
Authority
GB
United Kingdom
Prior art keywords
station
calling
main station
outstations
contacts
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
GB25506/51A
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.)
Siemens and Halske AG
Siemens AG
Original Assignee
Siemens and Halske AG
Siemens AG
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 Siemens and Halske AG, Siemens AG filed Critical Siemens and Halske AG
Publication of GB702571A publication Critical patent/GB702571A/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

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

702,571. Direct call systems; loudspeaker systems. SIEMENS & HALSKE AKT.-GES. Oct. 31, 1951 [Nov. 1, 1950], No. 25506/51. Class 40 (4) In a telephone system comprising a batteryfed main station and outstations employing loudspeakers both as transmitters and receivers but not including amplifiers, each of a number of outstations along a common line is connectible thereto by a pair of contacts K1, K2, which simultaneously close a signal circuit fed from the main station. Each of a pair of such lines a1, b1; a2, b2 is terminated at the main station Hst by a relay R1 which indicates that a station is calling on that line by lighting calling lamp Sz1 and ringing bell S. A calling station is connected by a switch A and switch U, besides energizing the microphone circuit, disconnects the bell S. A choke D1 prevents absorption of incoming speech by the microphone circuit. The operation of contacts K by a hinged protecting cover over the loudspeakers is suggested and Specification 571,547 is referred to.
GB25506/51A 1950-11-01 1951-10-31 Improvements in or relating to loudspeaking telephone installations Expired GB702571A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE702571X 1950-11-01

Publications (1)

Publication Number Publication Date
GB702571A true GB702571A (en) 1954-01-20

Family

ID=6612878

Family Applications (1)

Application Number Title Priority Date Filing Date
GB25506/51A Expired GB702571A (en) 1950-11-01 1951-10-31 Improvements in or relating to loudspeaking telephone installations

Country Status (1)

Country Link
GB (1) GB702571A (en)

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