3637943

Information

• Patent Grant
• 3637943

• References
• Source

• Patent Number

  3,637,943

• Date Filed

  Not available

• Date Issued

  Tuesday, January 25, 1972
  52 years ago

• CPC

  • H04Q1/4465 - the same frequency being used for all signalling information
  • H03H7/46 - Networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
  • H03H11/34 - Networks for connecting several sources or loads working on different frequencies or frequency bands, to a common load or source
  • H03K5/1565 - the output pulses having a constant duty cycle
  • H04Q1/446 - using one signalling frequency

• US Classifications

  • 379 - Telephonic communications