1438976

Information

• Patent Grant
• 1438976

• References
• Source

• Patent Number

  1,438,976

• Date Filed

  Not available

• Date Issued

  Tuesday, December 19, 1922
  102 years ago

• CPC

  • G05F1/26 - combined with discharge tubes or semiconductor devices

• US Classifications

  • 323 - Electricity: power supply or regulation systems
  • 315 - Electric lamp and discharge devices: systems
  • 324 - Electricity: measuring and testing