GB912755A - Improvements in or relating to circuit arrangements for automatic signalling systems - Google Patents

Improvements in or relating to circuit arrangements for automatic signalling systems

Info

Publication number
GB912755A
GB912755A GB34006/59A GB3400659A GB912755A GB 912755 A GB912755 A GB 912755A GB 34006/59 A GB34006/59 A GB 34006/59A GB 3400659 A GB3400659 A GB 3400659A GB 912755 A GB912755 A GB 912755A
Authority
GB
United Kingdom
Prior art keywords
transistor
circuits
tone
series
base
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
GB34006/59A
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.)
Philips Electrical Industries Ltd
Original Assignee
Philips Electrical Industries 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 Philips Electrical Industries Ltd filed Critical Philips Electrical Industries Ltd
Publication of GB912755A publication Critical patent/GB912755A/en
Expired legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q3/00Selecting arrangements
    • H04Q3/42Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker
    • H04Q3/52Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker using static devices in switching stages, e.g. electronic switching arrangements
    • H04Q3/521Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker using static devices in switching stages, e.g. electronic switching arrangements using semiconductors in the switching stages
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M19/00Current supply arrangements for telephone systems
    • H04M19/02Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q1/00Details of selecting apparatus or arrangements
    • H04Q1/18Electrical details
    • H04Q1/30Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/442Signalling arrangements; Manipulation of signalling currents using alternate current with out-of-voice band signalling frequencies
    • H04Q1/4423Signalling arrangements; Manipulation of signalling currents using alternate current with out-of-voice band signalling frequencies using one signalling frequency

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
  • Amplifiers (AREA)

Abstract

912,755. Valve and transistor amplifying circuits. PHILIPS ELECTRICAL INDUSTRIES Ltd. Oct. 7, 1959 [Oct. 10, 1958], No. 34006/59. Class 40 (6). [Also in Group XXXIX] Signalling tone is passed over the cathode or emitter circuit of a valve or transistor amplifier to a line across which a variable number of load circuits may be connected in parallel, each load being connected in series with a resistor shunter by a capacitor such that a change in the number of load circuits produces a change in D.C. over the line which equals the resulting change in amplitude of the tone signal. As shown in Fig. 1, a tone source SB drives the base of a transistor T, the emitter circuit of which is loaded by subscribers' lines B1, B2 . . ., in series with resistors S and capacitors C in circuits coupled to the lines by transformers TR. Fig. 3 shows the static characteristics L11, L21, L31 ... of emitter current against the bias and signal potential V between ground and the transistor base. Provision of series resistors S shunted by capacitors C gives a set of dynamic characteristics L12, L22, L32 . . ., which have a common intersection G on the V-axis. By making the bias V1 exceed the co-ordinate value of G by the amplitude of the tone source the required relation between A.C. and D.C. in the emitter path is achieved. The load circuits are connected up by switches K which may comprise the diode arrangement of Fig. 4 where a flip-flop FF controls diodes G1 and G2. In this arrangement a rectifier G3 provides the voltage necessary between collector and base of transistor T.
GB34006/59A 1958-10-10 1959-10-07 Improvements in or relating to circuit arrangements for automatic signalling systems Expired GB912755A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL232178 1958-10-10

Publications (1)

Publication Number Publication Date
GB912755A true GB912755A (en) 1962-12-12

Family

ID=19751383

Family Applications (1)

Application Number Title Priority Date Filing Date
GB34006/59A Expired GB912755A (en) 1958-10-10 1959-10-07 Improvements in or relating to circuit arrangements for automatic signalling systems

Country Status (6)

Country Link
JP (1) JPS3623516B1 (en)
CH (1) CH375046A (en)
DE (1) DE1146925B (en)
FR (1) FR1237437A (en)
GB (1) GB912755A (en)
NL (2) NL104005C (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1194917B (en) * 1963-09-25 1965-06-16 Merk Ag Telefonbau Friedrich Circuit arrangement for telephone switching systems

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1138579A (en) * 1955-12-14 1957-06-17 Cie Ind Des Telephones Inrush current sending device

Also Published As

Publication number Publication date
FR1237437A (en) 1960-07-29
JPS3623516B1 (en) 1961-12-11
NL104005C (en)
NL232178A (en)
DE1146925B (en) 1963-04-11
CH375046A (en) 1964-02-15

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