GB507132A - - Google Patents

Info

Publication number
GB507132A
GB507132A GB507132DA GB507132A GB 507132 A GB507132 A GB 507132A GB 507132D A GB507132D A GB 507132DA GB 507132 A GB507132 A GB 507132A
Authority
GB
United Kingdom
Prior art keywords
relay
circuit
operates
spacing
subscriber
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.)
Active
Application number
Other languages
English (en)
Publication of GB507132A publication Critical patent/GB507132A/en
Active legal-status Critical Current

Links

Landscapes

  • Interface Circuits In Exchanges (AREA)
GB507132D Active GB507132A (en:Method)

Publications (1)

Publication Number Publication Date
GB507132A true GB507132A (en:Method)

Family

ID=1747645

Family Applications (1)

Application Number Title Priority Date Filing Date
GB507132D Active GB507132A (en:Method)

Country Status (1)

Country Link
GB (1) GB507132A (en:Method)

Similar Documents

Publication Publication Date Title
GB1180140A (en) Automatic Signal Transmission System
US3865995A (en) Universal subscriber{3 s line circuit in a key telephone system
GB507132A (en:Method)
US4214127A (en) Intrinsically safe telephone network
US3278690A (en) Communication system having common amplifier means
GB388752A (en) Improvements in or relating to telephone systems
US2247507A (en) Telephone system
US2024581A (en) Telegraph toll system
US2200820A (en) Automatic telephone system
US1895112A (en) Printing telegraph exchange system
US2410866A (en) Telephone system
US2241258A (en) Teletypewriter switching system
US1996516A (en) Printing telegraph private branch exchange system
US2822423A (en) Fire and police intercommunication system
US2143000A (en) Telegraph system
US1592646A (en) Automatic telephone system
US2342586A (en) Repeater system
US1895097A (en) Printing telegraph exchange switching system
GB527336A (en) Printing telegraph system
US3571531A (en) Selective automatic service observing in communication systems
US2093084A (en) System for giving teletypewriter service over telephone lines
US1931603A (en) Telephone system
US3997735A (en) Telephone station make-busy circuit
US1998086A (en) Telegraph exchange system
US1617413A (en) Telephone system