Classifications

• • 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
  • H04Q1/38—Signalling arrangements; Manipulation of signalling currents using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
  • G01R19/145—Indicating the presence of current or voltage
  • G01R19/155—Indicating the presence of voltage
• • 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
  • H04M3/302—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for subscriber's lines, for the local loop using modulation techniques for copper pairs
  • H04M3/303—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for subscriber's lines, for the local loop using modulation techniques for copper pairs and using PCM multiplexers, e.g. pair gain systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04Q—SELECTING
  • H04Q11/00—Selecting arrangements for multiplex systems
  • H04Q11/02—Selecting arrangements for multiplex systems for frequency-division multiplexing
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04Q—SELECTING
  • H04Q5/00—Selecting arrangements wherein two or more subscriber stations are connected by the same line to the exchange
  • H04Q5/24—Selecting arrangements wherein two or more subscriber stations are connected by the same line to the exchange for two-party-line systems

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Signal Processing (AREA)
• Monitoring And Testing Of Exchanges (AREA)
• Devices For Supply Of Signal Current (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=5778575

Family Applications (2)

Family Applications Before (1)

Country Status (7)

Families Citing this family (3)

• 1970
  • 1970-07-31 DE DE19702038218 patent/DE2038218B2/de not_active Withdrawn
• 1971
  • 1971-07-02 CH CH975671A patent/CH535519A/de not_active IP Right Cessation
  • 1971-07-28 JP JP46056695A patent/JPS5141488B1/ja active Pending
  • 1971-07-29 GB GB3570471A patent/GB1329955A/en not_active Expired
  • 1971-07-29 BE BE770678A patent/BE770678A/xx unknown
  • 1971-07-30 NL NL7110582A patent/NL150295B/nl unknown
  • 1971-07-30 SE SE981771A patent/SE380156B/xx unknown
• 1976
  • 1976-02-05 NL NL7601193A patent/NL7601193A/nl unknown

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