2641653

Information

• Patent Grant
• 2641653

• References
• Source

• Patent Number

  2,641,653

• Date Filed

  Not available

• Date Issued

  Tuesday, June 9, 1953
  72 years ago

• CPC

  • H04Q5/06 - Signalling by amplitude or polarity of dc
  • H04M19/04 - ringing-current generated at substation

• US Classifications

  • 379 - Telephonic communications