Classifications

• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
  • H03L5/00—Automatic control of voltage, current, or power
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04M—TELEPHONIC COMMUNICATION
  • H04M1/00—Substation equipment, e.g. for use by subscribers
  • H04M1/26—Devices for calling a subscriber
  • H04M1/30—Devices which can set up and transmit only one digit at a time
  • H04M1/50—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies
  • H04M1/505—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies signals generated in digital form
• • 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
  • H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
  • H04Q1/457—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals
  • H04Q1/4575—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals which are transmitted in digital form

Landscapes

• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Computer Networks & Wireless Communication (AREA)
• Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
• Digital Transmission Methods That Use Modulated Carrier Waves (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=26215768

Family Applications (1)

Country Status (4)

Families Citing this family (1)

• 1971
  • 1971-05-25 NL NL7107106A patent/NL7107106A/xx not_active Application Discontinuation
  • 1971-05-27 SE SE686471A patent/SE373711B/xx unknown
  • 1971-05-28 GB GB1814171A patent/GB1338633A/en not_active Expired
  • 1971-05-28 DE DE19712126717 patent/DE2126717A1/de active Pending

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