JPS5592065A - Subscriber's line test circuit - Google Patents

Subscriber's line test circuit

Info

Publication number
JPS5592065A
JPS5592065A JP16580978A JP16580978A JPS5592065A JP S5592065 A JPS5592065 A JP S5592065A JP 16580978 A JP16580978 A JP 16580978A JP 16580978 A JP16580978 A JP 16580978A JP S5592065 A JPS5592065 A JP S5592065A
Authority
JP
Japan
Prior art keywords
insulation resistance
line
inter
zab
vout
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.)
Granted
Application number
JP16580978A
Other languages
Japanese (ja)
Other versions
JPS5923665B2 (en
Inventor
Takeshi Sakai
Eiji Inishi
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 JP53165809A priority Critical patent/JPS5923665B2/en
Publication of JPS5592065A publication Critical patent/JPS5592065A/en
Publication of JPS5923665B2 publication Critical patent/JPS5923665B2/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/26—Arrangements for supervision, monitoring or testing with means for applying test signals or for measuring
    • H04M3/28—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor
    • H04M3/30—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for subscriber's lines, for the local loop

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Measurement Of Resistance Or Impedance (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
  • Monitoring And Testing Of Transmission In General (AREA)

Abstract

PURPOSE:To measure accurately an inter-line insulation resistance without the influence of the insulation resistance between one line and the ground by providing a balanced emitter follower circuit and by utilizing the output of this circuit to measure the inter-line insulation resistance. CONSTITUTION:Positive power source +V1 and negative power source -V2 are connected to a subscriber's line consisting of two wires through series resistances Z1 and Z2 respectively. Voltages of both wires are inputted to bases of transistors Q1 and Q2 constituting an emitter follower, and outputs generated in their emitters are amplified by transistors Q3 and Q4 of a differential amplifier to generate output voltage Vout. Since the input impedance of collector-connected Q1 and Q2 is high sufficiently, the insulation resistance is not affected. Potential difference applied across bases of Q1 and Q2 is large when inter-line insulation resistance ZAB, and consequently, the current of transistor Q3 is large and the current of Q4 is small. Therefore, output voltage taken out from the collector of Q3 is small. Reversely, Vout is larger when resistance ZAB is small. This output voltage Vout and insulation resistance ZAB have a fixed relation, so that inter-line insulation can be measured by measuring Vout.
JP53165809A 1978-12-30 1978-12-30 Subscriber line test circuit Expired JPS5923665B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP53165809A JPS5923665B2 (en) 1978-12-30 1978-12-30 Subscriber line test circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP53165809A JPS5923665B2 (en) 1978-12-30 1978-12-30 Subscriber line test circuit

Publications (2)

Publication Number Publication Date
JPS5592065A true JPS5592065A (en) 1980-07-12
JPS5923665B2 JPS5923665B2 (en) 1984-06-04

Family

ID=15819400

Family Applications (1)

Application Number Title Priority Date Filing Date
JP53165809A Expired JPS5923665B2 (en) 1978-12-30 1978-12-30 Subscriber line test circuit

Country Status (1)

Country Link
JP (1) JPS5923665B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0443639Y2 (en) * 1988-05-27 1992-10-15

Also Published As

Publication number Publication date
JPS5923665B2 (en) 1984-06-04

Similar Documents

Publication Publication Date Title
GB1058890A (en) Improvements in and relating to methods of measuring voltage
ATE24257T1 (en) SEMICONDUCTOR AMPLIFIER CIRCUIT.
JPS5592065A (en) Subscriber's line test circuit
JPS5592006A (en) Amplifier
US3506847A (en) Logarithmic converter
JPS5587052A (en) Measuring circuit for instantaneous power
US3564436A (en) High input impedance amplifier
JPS5539432A (en) Differential amplifier circuit
GB886287A (en) Voltage or current-sensitive controlling device
SU1170362A1 (en) Peak detector
DE3369039D1 (en) Integrated amplifier circuit
SU484566A1 (en) Differential amplifier
SU442363A1 (en) Non-electric measuring transducer in direct current voltage
JPS55134513A (en) Input bias adjusting circuit of amplifier
SU813692A1 (en) Voltage-to-current converter
SU1176347A1 (en) Multiplyng-dividing device
JPS56132006A (en) Differential amplifier
JPS54139362A (en) Signal amplifier
JPS5560314A (en) Protective device for amplifier circuit
JPS5737910A (en) Negative feedback amplifier
JPS54134684A (en) Card circuit of electrostatic capacity measuring apparatus
JPS5574224A (en) Signal amplifying circuit
JPS54132157A (en) Amplifier
JPS5735403A (en) Amplifier
JPS5683107A (en) Gain control circuit