GB375749A - Automatic coin freed telephone exchange - Google Patents

Automatic coin freed telephone exchange

Info

Publication number
GB375749A
GB375749A GB11879/32A GB1187932A GB375749A GB 375749 A GB375749 A GB 375749A GB 11879/32 A GB11879/32 A GB 11879/32A GB 1187932 A GB1187932 A GB 1187932A GB 375749 A GB375749 A GB 375749A
Authority
GB
United Kingdom
Prior art keywords
telephone exchange
automatic coin
coin freed
relay
magnet
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
GB11879/32A
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
Publication of GB375749A publication Critical patent/GB375749A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M17/00—Prepayment of wireline communication systems, wireless communication systems or telephone systems
    • H04M17/02—Coin-freed or check-freed systems, e.g. mobile- or card-operated phones, public telephones or booths
    • H04M17/023—Circuit arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Computer Security & Cryptography (AREA)
  • Signal Processing (AREA)
  • Audible And Visible Signals (AREA)

Abstract

375,749. Automatic exchange systems. AESCHLIMANN, W., 60, St³ssistrasse, Zurich, Switzerland. April 25, 1932, No. 11879. Convention date, May 16, 1931. [Class 40 (iv.)] The collecting magnet KM at a prepayment station is connected to the line through a neon lamp GL. At the end of a conversation, alternating current flows from a transformer TV over contact Z3, and a direct current circuit is closed through the magnet KM and a relay KR. Should this circuit not be completed, the non-operation of the relay KR gives an alarm.
GB11879/32A 1931-05-16 1932-04-25 Automatic coin freed telephone exchange Expired GB375749A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH375749X 1931-05-16

Publications (1)

Publication Number Publication Date
GB375749A true GB375749A (en) 1932-06-30

Family

ID=4513563

Family Applications (1)

Application Number Title Priority Date Filing Date
GB11879/32A Expired GB375749A (en) 1931-05-16 1932-04-25 Automatic coin freed telephone exchange

Country Status (3)

Country Link
CH (1) CH154355A (en)
FR (1) FR735892A (en)
GB (1) GB375749A (en)

Also Published As

Publication number Publication date
CH154355A (en) 1932-04-30
FR735892A (en) 1932-11-16

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