1839904

Information

• Patent Grant
• 1839904

• References
• Source

• Patent Number

  1,839,904

• Date Filed

  Not available

• Date Issued

  Tuesday, January 5, 1932
  92 years ago

• CPC

  • H01J21/12 - Tubes with variable amplification factor
  • H01J2893/0032 - Tubes with variable amplification factor

• US Classifications

  • 313 - Electric lamp and discharge devices