GB1495994A - Telephone systems - Google Patents

Telephone systems

Info

Publication number
GB1495994A
GB1495994A GB10420/75A GB1042075A GB1495994A GB 1495994 A GB1495994 A GB 1495994A GB 10420/75 A GB10420/75 A GB 10420/75A GB 1042075 A GB1042075 A GB 1042075A GB 1495994 A GB1495994 A GB 1495994A
Authority
GB
United Kingdom
Prior art keywords
counter
signal
incoming
count
ringing
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
GB10420/75A
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.)
Siemens Corp
Original Assignee
Siemens Corp
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 Siemens Corp filed Critical Siemens Corp
Publication of GB1495994A publication Critical patent/GB1495994A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/58—Arrangements providing connection between main exchange and sub-exchange or satellite
    • H04Q3/62—Arrangements providing connection between main exchange and sub-exchange or satellite for connecting to private branch exchanges
    • H04Q3/625—Arrangements in the private branch exchange
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/446—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency
    • H04Q1/448—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency with conversion of a single frequency signal into a digital signal

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • Astronomy & Astrophysics (AREA)
  • General Physics & Mathematics (AREA)
  • Telephonic Communication Services (AREA)
  • Facsimiles In General (AREA)
GB10420/75A 1974-03-29 1975-03-13 Telephone systems Expired GB1495994A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2415368A DE2415368B1 (de) 1974-03-29 1974-03-29 Schaltungsanordnung für Fernsprechanlagen, insbesondere Fernsprechnebenstellenanlagen, zur einwandfreien Erkennung des ankommenden Ruf wechselstromes bei ankommender Belegung einer Verbindungsleitung

Publications (1)

Publication Number Publication Date
GB1495994A true GB1495994A (en) 1977-12-21

Family

ID=5911640

Family Applications (1)

Application Number Title Priority Date Filing Date
GB10420/75A Expired GB1495994A (en) 1974-03-29 1975-03-13 Telephone systems

Country Status (11)

Country Link
AT (1) AT334983B (cs)
BE (1) BE827366A (cs)
CH (1) CH588196A5 (cs)
DE (1) DE2415368B1 (cs)
DK (1) DK115975A (cs)
FR (1) FR2266392B1 (cs)
GB (1) GB1495994A (cs)
IT (1) IT1034679B (cs)
LU (1) LU72147A1 (cs)
NL (1) NL7503440A (cs)
SE (1) SE7503635L (cs)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT380978B (de) * 1984-04-27 1986-08-11 Uher Ag Einrichtung zur bewertung von empfangssignalen in tonfrequenz-rundsteuerempfaengern (tre)

Also Published As

Publication number Publication date
IT1034679B (it) 1979-10-10
LU72147A1 (cs) 1975-08-20
DK115975A (cs) 1975-09-30
CH588196A5 (cs) 1977-05-31
SE7503635L (cs) 1975-09-30
FR2266392A1 (cs) 1975-10-24
BE827366A (fr) 1975-09-29
DE2415368B1 (de) 1975-07-03
ATA163075A (de) 1976-06-15
FR2266392B1 (cs) 1977-11-18
NL7503440A (nl) 1975-10-01
AT334983B (de) 1977-02-10

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee