ES343441A1 - Improvements in telephone subscriber's instrument - Google Patents

Improvements in telephone subscriber's instrument

Info

Publication number
ES343441A1
ES343441A1 ES343441A ES343441A ES343441A1 ES 343441 A1 ES343441 A1 ES 343441A1 ES 343441 A ES343441 A ES 343441A ES 343441 A ES343441 A ES 343441A ES 343441 A1 ES343441 A1 ES 343441A1
Authority
ES
Spain
Prior art keywords
amplifier
line
coupled
current
circuit
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
ES343441A
Other languages
Spanish (es)
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.)
Nokia Spain SA
Original Assignee
Alcatel Espana SA
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 Alcatel Espana SA filed Critical Alcatel Espana SA
Publication of ES343441A1 publication Critical patent/ES343441A1/en
Expired 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
    • H04M19/04—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone the ringing-current being generated at the substations
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/58—Anti-side-tone circuits
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Amplifiers (AREA)

Abstract

In a substation which includes moving coil type transmit and receive transducers, outgoing speech is amplified by an amplifier which derives its D.C. power from the line and which consists of two stages of transistors that are D.C. coupled by a voltage dependent resistor which also serves for compensating for different lengths of lines, the emitters of the two transistors being coupled by a positive feedback A.G.C. circuit which includes a further voltage dependent resistor. Calling tone generator.-This comprises an audio transducer TG which forms part of the resonant circuit of an exchange battery powered transistor oscillator T1. The transducer produces a variable frequency tone continuously once it has responded to the initial negative pulse of ringing current. Transmit amplifier.-This consists of a dynamic microphone MA which is coupled via a low impedance network R19, C9 to a two-stage D.C. coupled amplifier T4, T3. (MA acts virtually as a constant current source and it is decoupled from the exchange line D.C. by capacitor C9). The amplifier includes a negative feedback path R13, a positive feedback path which provides A.G.C. (VR2) and is voltage gain stabilized because of the unbypassed resistors R12, R17. Operating current is derived from the line via a full wave rectifier D3-D6 and is supplied (at least to T4's collector and T3's base) via choke L1 and resistors R16, VR1. A measure of high frequency compensation is provided by C6. Anti-sidetone circuit consists of a transistor T2 which has a gain equal to that of T3 whereby a minimum of sidetone appears in the receiver RA whatever the length of line to which the set is connected. Receive amplifier.-This is only operative for long lines and comprises transistors T4, T2. A portion of the input signal is applied to T4 across R13, R17 and is amplified by T4 since T4's gain is increased considerably (via its positive feedback circuit) on long lines. The signal path to RA ordinarily consists in: A wire junction D5, D6 RA RB R9 and R11, C5 C7 junction of D3, D4. Voltage dependent resistors VR3, VR4 act as click suppressors on incoming signals. Long line compensation is provided, by VR5 which stabilizes the collector current of T4, by VR1 which limits internal power dissipation on short lines and, by the resistance of L1, R16, R12 (and VR1) which govern the ratio of T4's collector current to T3's base current and hence the stability of the D.C. potential at the set's terminals.
ES343441A 1966-07-26 1967-07-26 Improvements in telephone subscriber's instrument Expired ES343441A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
AU8852/66A AU415632B1 (en) 1966-07-26 1966-07-26 Improvements in telecommunication transceivers and telephone subsets incorporating same

Publications (1)

Publication Number Publication Date
ES343441A1 true ES343441A1 (en) 1968-09-01

Family

ID=3699566

Family Applications (1)

Application Number Title Priority Date Filing Date
ES343441A Expired ES343441A1 (en) 1966-07-26 1967-07-26 Improvements in telephone subscriber's instrument

Country Status (5)

Country Link
AT (1) AT286378B (en)
AU (1) AU415632B1 (en)
DE (1) DE1537613A1 (en)
ES (1) ES343441A1 (en)
GB (1) GB1145587A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110677062B (en) * 2019-11-08 2024-06-21 广东鉴面智能科技有限公司 Low standby power consumption switching stabilized voltage supply

Also Published As

Publication number Publication date
GB1145587A (en) 1969-03-19
DE1537613A1 (en) 1969-08-28
AU415632B1 (en) 1971-07-28
AT286378B (en) 1970-12-10

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