2500504

Information

• Patent Grant
• 2500504

• References
• Source

• Patent Number

  2,500,504

• Date Filed

  Not available

• Date Issued

  Tuesday, March 14, 1950
  75 years ago

• CPC

  • H04B1/1623 - using tubes

• US Classifications

  • 455 - Telecommunications
  • 315 - Electric lamp and discharge devices: systems