JPS5696571A - Signal transmission system - Google Patents

Signal transmission system

Info

Publication number
JPS5696571A
JPS5696571A JP17291179A JP17291179A JPS5696571A JP S5696571 A JPS5696571 A JP S5696571A JP 17291179 A JP17291179 A JP 17291179A JP 17291179 A JP17291179 A JP 17291179A JP S5696571 A JPS5696571 A JP S5696571A
Authority
JP
Japan
Prior art keywords
fed
pattern
dial tone
signal
decoder
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
JP17291179A
Other languages
Japanese (ja)
Inventor
Narutomo Ro
Kunihiko Kawanishi
Makoto Ichikawa
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 JP17291179A priority Critical patent/JPS5696571A/en
Publication of JPS5696571A publication Critical patent/JPS5696571A/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
    • H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Time-Division Multiplex Systems (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

PURPOSE:To avoid the lowering in the level even if a signal is fed to a plurality of loads at the reception side, by providing the signal pattern generator producing the pattern of frequency signal below the audio band at the reception side. CONSTITUTION:Dial tone pattern is read out in a dial tone pattern generator 45 in synchronizing with clocks. This pattern is fed to a decoder 43 of each channel via an NOR circuit 47. The dial tone in the frequency below audio band from the exchanger, e.g., 50Hz, is delivered to a multiplexer 49 via a PCM transmission line 50 with the signal bit. It is fed to an NOR circuit 46 and an inverter 48 with separation. This signal bit is fed to telephone sets via a decoder 43 and low pass filter 44. Thus, even if a plurality of channels are in off-hook at the same time and a pattern is fed from the generator 45, no level of the dial tone transmitted to the telephone sets is lowered.
JP17291179A 1979-12-28 1979-12-28 Signal transmission system Pending JPS5696571A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17291179A JPS5696571A (en) 1979-12-28 1979-12-28 Signal transmission system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17291179A JPS5696571A (en) 1979-12-28 1979-12-28 Signal transmission system

Publications (1)

Publication Number Publication Date
JPS5696571A true JPS5696571A (en) 1981-08-04

Family

ID=15950622

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17291179A Pending JPS5696571A (en) 1979-12-28 1979-12-28 Signal transmission system

Country Status (1)

Country Link
JP (1) JPS5696571A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0422231A (en) * 1990-05-17 1992-01-27 Nec Corp Pcm transmission system and channel board of pcm terminal equipment
JPH04364619A (en) * 1991-06-11 1992-12-17 Nec Corp In-band signal system channel panel for pcm terminal station equipment

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0422231A (en) * 1990-05-17 1992-01-27 Nec Corp Pcm transmission system and channel board of pcm terminal equipment
JPH04364619A (en) * 1991-06-11 1992-12-17 Nec Corp In-band signal system channel panel for pcm terminal station equipment

Similar Documents

Publication Publication Date Title
US2817711A (en) Band compression system
ES8602328A1 (en) Multiplexer system for automatic meter reading.
JPS5696571A (en) Signal transmission system
JPS6457844A (en) Digital signal multiplexer
AU552868B2 (en) Digital colour camera
JPS5521610A (en) Transmission system of audio packet
JPS5228208A (en) Fm multiplex stereo demodulator circuit
JPS5696551A (en) Multiplex communication device
JPS57112148A (en) System for multiplexing digital signal
JPS5673937A (en) Pcm communication system
JPS5242308A (en) Multiplex frequency signal receiver
JPS56120239A (en) Simple privacy telephone system
JPS5715563A (en) Coin deposition type facsimile system
JPS645250A (en) Howling prevention circuit for loudspeaker system telephone set
JPS5364018A (en) Speaker system
JPS57188150A (en) Multiplex signal transmission system
JPS5427702A (en) Overall digital switchboard
JPS56119539A (en) Four-wire transmission system
JPS5558658A (en) Subscriber's line telephone transmission system
JPS5588451A (en) Privacy telephone system
JPS5413714A (en) Multi-frequency signal reception system
JPS57171870A (en) Signal deciding circuit for digital multifrequency signal receiver
JPS57204649A (en) Rejector circuit of supervisory signal
JPS5742246A (en) Multiplex communication device
JPS5224427A (en) Frequency converter circuit