2489891

Information

• Patent Grant
• 2489891

• References
• Source

• Patent Number

  2,489,891

• Date Filed

  Not available

• Date Issued

  Tuesday, November 29, 1949
  75 years ago

• CPC

  • H01J17/54 - having one or more control electrodes

• US Classifications

  • 313 - Electric lamp and discharge devices
  • 174 - Electricity: conductors and insulators