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
  • H04M1/26—Devices for calling a subscriber
• • 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
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04M—TELEPHONIC COMMUNICATION
  • H04M1/00—Substation equipment, e.g. for use by subscribers
  • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers

Landscapes

• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Devices For Supply Of Signal Current (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=7456695

Family Applications (1)

Country Status (4)

Families Citing this family (2)

Family Cites Families (11)

• 1959
  • 1959-08-04 DE DEST15425A patent/DE1108748B/de active Pending
• 1960
  • 1960-07-15 US US43217A patent/US3153703A/en not_active Expired - Lifetime
  • 1960-07-29 GB GB26432/60A patent/GB954211A/en not_active Expired
  • 1960-08-04 CH CH883460A patent/CH385927A/de unknown

Also Published As

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