2479881

Information

• Patent Grant
• 2479881

• References
• Source

• Patent Number

  2,479,881

• Date Filed

  Not available

• Date Issued

  Tuesday, August 23, 1949
  75 years ago

• CPC

  • H04Q9/06 - Calling by using amplitude or polarity of dc
  • Y10T307/74 - Switching systems

• US Classifications

  • 307 - Electrical transmission or interconnection systems