2609618

Information

• Patent Grant
• 2609618

• References
• Source

• Patent Number

  2,609,618

• Date Filed

  Not available

• Date Issued

  Tuesday, September 9, 1952
  72 years ago

• CPC

  • G09B19/00 - Teaching not covered by other main groups of this subclass
  • G09B19/0007 - Signalling

• US Classifications

  • 434 - Education and demonstration
  • 346 - Recorders