GB1050045A - - Google Patents

Info

Publication number
GB1050045A
GB1050045A GB1050045DA GB1050045A GB 1050045 A GB1050045 A GB 1050045A GB 1050045D A GB1050045D A GB 1050045DA GB 1050045 A GB1050045 A GB 1050045A
Authority
GB
United Kingdom
Prior art keywords
circuit
ringer
isolated
april
relay
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)
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.)
Publication of GB1050045A publication Critical patent/GB1050045A/en
Active 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
    • H04M1/68—Circuit arrangements for preventing eavesdropping

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
GB1050045D 1964-04-17 Active GB1050045A (enExample)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEST21984A DE1208360B (de) 1964-04-17 1964-04-17 Schaltungsanordnung zur Verhinderung des Abhoerens von Gespraechen

Publications (1)

Publication Number Publication Date
GB1050045A true GB1050045A (enExample)

Family

ID=7459196

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1050045D Active GB1050045A (enExample) 1964-04-17

Country Status (2)

Country Link
DE (1) DE1208360B (enExample)
GB (1) GB1050045A (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3842216A (en) * 1972-08-07 1974-10-15 Ford Ind Inc Frequency-selective ringing current sensor for telephone line

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3842216A (en) * 1972-08-07 1974-10-15 Ford Ind Inc Frequency-selective ringing current sensor for telephone line

Also Published As

Publication number Publication date
DE1208360B (de) 1966-01-05

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