GB355181A - Improvements in switching arrangements for telephone systems - Google Patents

Improvements in switching arrangements for telephone systems

Info

Publication number
GB355181A
GB355181A GB8512/31A GB851231A GB355181A GB 355181 A GB355181 A GB 355181A GB 8512/31 A GB8512/31 A GB 8512/31A GB 851231 A GB851231 A GB 851231A GB 355181 A GB355181 A GB 355181A
Authority
GB
United Kingdom
Prior art keywords
valve
relay
subscriber
prepayment
march
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
GB8512/31A
Other languages
English (en)
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.)
Telefonaktiebolaget LM Ericsson AB
Original Assignee
Telefonaktiebolaget LM Ericsson AB
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 Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Publication of GB355181A publication Critical patent/GB355181A/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)
  • Interface Circuits In Exchanges (AREA)
GB8512/31A 1930-03-21 1931-03-19 Improvements in switching arrangements for telephone systems Expired GB355181A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE355181X 1930-03-21

Publications (1)

Publication Number Publication Date
GB355181A true GB355181A (en) 1931-08-20

Family

ID=20308758

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8512/31A Expired GB355181A (en) 1930-03-21 1931-03-19 Improvements in switching arrangements for telephone systems

Country Status (6)

Country Link
US (1) US1855087A (enrdf_load_stackoverflow)
BE (1) BE378410A (enrdf_load_stackoverflow)
DE (1) DE583068C (enrdf_load_stackoverflow)
FR (1) FR713494A (enrdf_load_stackoverflow)
GB (1) GB355181A (enrdf_load_stackoverflow)
NL (1) NL34614C (enrdf_load_stackoverflow)

Also Published As

Publication number Publication date
BE378410A (enrdf_load_stackoverflow)
NL34614C (enrdf_load_stackoverflow)
DE583068C (de) 1933-08-28
FR713494A (fr) 1931-10-28
US1855087A (en) 1932-04-19

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