GB732028A - - Google Patents

Info

Publication number
GB732028A
GB732028A GB732028DA GB732028A GB 732028 A GB732028 A GB 732028A GB 732028D A GB732028D A GB 732028DA GB 732028 A GB732028 A GB 732028A
Authority
GB
United Kingdom
Prior art keywords
relay
amplifier
relays
contact
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.)
Active
Application number
Other languages
English (en)
Publication of GB732028A publication Critical patent/GB732028A/en
Active legal-status Critical Current

Links

Landscapes

  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
GB732028D Active GB732028A (enExample)

Publications (1)

Publication Number Publication Date
GB732028A true GB732028A (enExample)

Family

ID=1751258

Family Applications (1)

Application Number Title Priority Date Filing Date
GB732028D Active GB732028A (enExample)

Country Status (1)

Country Link
GB (1) GB732028A (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3296380A (en) * 1962-03-14 1967-01-03 Int Standard Electric Corp Automatic loud speaker intercommunication telephone system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3296380A (en) * 1962-03-14 1967-01-03 Int Standard Electric Corp Automatic loud speaker intercommunication telephone system

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