JPS5761371A - Power supply circuit for telephone - Google Patents

Power supply circuit for telephone

Info

Publication number
JPS5761371A
JPS5761371A JP13622980A JP13622980A JPS5761371A JP S5761371 A JPS5761371 A JP S5761371A JP 13622980 A JP13622980 A JP 13622980A JP 13622980 A JP13622980 A JP 13622980A JP S5761371 A JPS5761371 A JP S5761371A
Authority
JP
Japan
Prior art keywords
letter
coil
telephone
coils
current
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.)
Pending
Application number
JP13622980A
Other languages
Japanese (ja)
Inventor
Kenji Narita
Shuji Kimura
Takeshi Sakai
Nobuhisa Kamoi
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP13622980A priority Critical patent/JPS5761371A/en
Publication of JPS5761371A publication Critical patent/JPS5761371A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/001—Current supply source at the exchanger providing current to substations
    • H04M19/003—Arrangements for compensation of the DC flux in line transformers

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

PURPOSE:To replace a letter coil with a small one, by erasing DC magnetic field occurred with each other by setting the current in the same direction in the letter coil, fellow of telephone. CONSTITUTION:A capacitor 4 is installed between a letter coil 3 and a telephone 1 and install letter coils 5 and 6 on the both extremes of the capacitor 4. A letter coil 5 is connected to the letter coil 3 and connect a letter coil 6 to a negative power source. Then, DC current is flowed in order of letter coil 2 telephone 1 letter coil 5 letter coil 3 letter coil 6. Therefore, in the letter coils 2 and 3, and 5 and 6, as shown in the figure with an arrow mark, a current is flowed in the same direction and respective DC magnetic fields occurred are erased. By this reason, the condition of the letter coils 2 and 3, and 5 and 6 becomes the same condition as that a current does not practically flow in. Then, even if the voice signal is doubled, the margin to a saturation point becomes large and letter coils can be replaced with small ones.
JP13622980A 1980-09-30 1980-09-30 Power supply circuit for telephone Pending JPS5761371A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13622980A JPS5761371A (en) 1980-09-30 1980-09-30 Power supply circuit for telephone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13622980A JPS5761371A (en) 1980-09-30 1980-09-30 Power supply circuit for telephone

Publications (1)

Publication Number Publication Date
JPS5761371A true JPS5761371A (en) 1982-04-13

Family

ID=15170299

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13622980A Pending JPS5761371A (en) 1980-09-30 1980-09-30 Power supply circuit for telephone

Country Status (1)

Country Link
JP (1) JPS5761371A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02165758A (en) * 1988-12-20 1990-06-26 Nec Corp Isdn network terminating equipment

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3548109A (en) * 1966-09-19 1970-12-15 Siemens Ag Telephone relay and associated circuit

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3548109A (en) * 1966-09-19 1970-12-15 Siemens Ag Telephone relay and associated circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02165758A (en) * 1988-12-20 1990-06-26 Nec Corp Isdn network terminating equipment

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