1998993

Information

• Patent Grant
• 1998993

• References
• Source

• Patent Number

  1,998,993

• Date Filed

  Not available

• Date Issued

  Tuesday, April 23, 1935
  90 years ago

• CPC

  • H04L17/28 - using pneumatic or hydraulic translation

• US Classifications

  • 178 - Telegraphy
  • 370 - Multiplex communications