2142591

Information

• Patent Grant
• 2142591

• References
• Source

• Patent Number

  2,142,591

• Date Filed

  Not available

• Date Issued

  Tuesday, January 3, 1939
  86 years ago

• CPC

  • G11B3/78 - Multiple-track arrangements

• US Classifications

  • 369 - Dynamic information storage or retrieval
  • 434 - Education and demonstration