ZA704669B - Improvements in or relating to electric circuits for telephones - Google Patents

Improvements in or relating to electric circuits for telephones

Info

Publication number
ZA704669B
ZA704669B ZA704669A ZA704669A ZA704669B ZA 704669 B ZA704669 B ZA 704669B ZA 704669 A ZA704669 A ZA 704669A ZA 704669 A ZA704669 A ZA 704669A ZA 704669 B ZA704669 B ZA 704669B
Authority
ZA
South Africa
Prior art keywords
telephones
relating
electric circuits
circuits
electric
Prior art date
Application number
ZA704669A
Inventor
E Addington
Original Assignee
Gen Electric & English Elect
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 Gen Electric & English Elect filed Critical Gen Electric & English Elect
Publication of ZA704669B publication Critical patent/ZA704669B/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
    • H04M19/04—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone the ringing-current being generated at the substations

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
ZA704669A 1969-07-09 1970-07-07 Improvements in or relating to electric circuits for telephones ZA704669B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3464069 1969-07-09

Publications (1)

Publication Number Publication Date
ZA704669B true ZA704669B (en) 1971-03-31

Family

ID=10368157

Family Applications (1)

Application Number Title Priority Date Filing Date
ZA704669A ZA704669B (en) 1969-07-09 1970-07-07 Improvements in or relating to electric circuits for telephones

Country Status (2)

Country Link
GB (1) GB1318870A (en)
ZA (1) ZA704669B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1071838B (en) * 1976-11-12 1985-04-10 Cselt Centro Studi Lab Telecom UNWANTED RING PULSE SUPPRESSOR FOR TELEPHONE EQUIPMENT
US4140884A (en) * 1977-09-14 1979-02-20 Telephone And Data Products Electronic tone ringer

Also Published As

Publication number Publication date
GB1318870A (en) 1973-05-31

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