3526721

Information

• Patent Grant
• 3526721

• References
• Source

• Patent Number

  3,526,721

• Date Filed

  Not available

• Date Issued

  Tuesday, September 1, 1970
  55 years ago

• CPC

  • H04Q3/00 - Selecting arrangements
  • H04Q5/06 - Signalling by amplitude or polarity of dc

• US Classifications

  • 379 - Telephonic communications