1988559

Information

• Patent Grant
• 1988559

• References
• Source

• Patent Number

  1,988,559

• Date Filed

  Not available

• Date Issued

  Tuesday, January 22, 1935
  90 years ago

• CPC

  • H03J9/007 - by voltages or currents with different frequencies or phases
  • H03J9/04 - using ultrasonic, sonic or infrasonic waves

• US Classifications

  • 455 - Telecommunications
  • 340 - Communications: electrical