Classifications

• • 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
  • H04M1/515—Devices for calling a subscriber by generating or selecting signals other than trains of pulses of similar shape, or signals other than currents of one or more different frequencies, e.g. generation of dc signals of alternating polarity, coded pulses or impedance dialling
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
  • H03K17/28—Modifications for introducing a time delay before switching
• • 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
  • H04Q—SELECTING
  • H04Q3/00—Selecting arrangements

Landscapes

• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Computer Networks & Wireless Communication (AREA)
• Devices For Supply Of Signal Current (AREA)
• Input From Keyboards Or The Like (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=19752541

Family Applications (1)

Country Status (3)

Family Cites Families (2)

• 0
  • NL NL255555D patent/NL255555A/xx unknown
• 1961
  • 1961-08-31 GB GB3138561A patent/GB957319A/en not_active Expired
  • 1961-09-01 DE DEN20502A patent/DE1134113B/de active Pending

Also Published As

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