GB493668A - Improvements in amplifying devices for use at telephone subscribers' stations - Google Patents

Improvements in amplifying devices for use at telephone subscribers' stations

Info

Publication number
GB493668A
GB493668A GB31154/37A GB3115437A GB493668A GB 493668 A GB493668 A GB 493668A GB 31154/37 A GB31154/37 A GB 31154/37A GB 3115437 A GB3115437 A GB 3115437A GB 493668 A GB493668 A GB 493668A
Authority
GB
United Kingdom
Prior art keywords
stations
amplifying devices
telephone subscribers
nov
winding
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
GB31154/37A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB493668A publication Critical patent/GB493668A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/6033—Substation equipment, e.g. for use by subscribers including speech amplifiers for providing handsfree use or a loudspeaker mode in telephone sets

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
GB31154/37A 1936-11-20 1937-11-12 Improvements in amplifying devices for use at telephone subscribers' stations Expired GB493668A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
BE228093X 1936-11-20

Publications (1)

Publication Number Publication Date
GB493668A true GB493668A (en) 1938-10-12

Family

ID=3866209

Family Applications (1)

Application Number Title Priority Date Filing Date
GB31154/37A Expired GB493668A (en) 1936-11-20 1937-11-12 Improvements in amplifying devices for use at telephone subscribers' stations

Country Status (5)

Country Link
BE (1) BE418493A (en:Method)
CH (1) CH228093A (en:Method)
FR (1) FR829576A (en:Method)
GB (1) GB493668A (en:Method)
NL (1) NL49768C (en:Method)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE965133C (de) * 1953-10-11 1957-06-06 Telefonbau & Normalzeit Gmbh Schaltungsanordnung fuer bevorzugte Sprechstellen in Fernsprechanlagen mit Waehlerbetrieb
DE1141681B (de) * 1961-04-07 1962-12-27 Huettenwerk Oberhausen Ag Fernsprechteilnehmerschaltung fuer Linien-Waehlanlagen mit Freisprecheinrichtung

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE965133C (de) * 1953-10-11 1957-06-06 Telefonbau & Normalzeit Gmbh Schaltungsanordnung fuer bevorzugte Sprechstellen in Fernsprechanlagen mit Waehlerbetrieb
DE1141681B (de) * 1961-04-07 1962-12-27 Huettenwerk Oberhausen Ag Fernsprechteilnehmerschaltung fuer Linien-Waehlanlagen mit Freisprecheinrichtung

Also Published As

Publication number Publication date
FR829576A (fr) 1938-06-30
BE418493A (en:Method)
NL49768C (en:Method)
CH228093A (de) 1943-07-31

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