1397575

Information

• Patent Grant
• 1397575

• References
• Source

• Patent Number

  1,397,575

• Date Filed

  Not available

• Date Issued

  Tuesday, November 22, 1921
  103 years ago

• CPC

  • H03F1/36 - in discharge-tube amplifiers
  • H03F1/40 - in discharge-tube amplifiers

• US Classifications

  • 330 - Amplifiers
  • 381 - Electrical audio signal processing systems and devices