2154877

Information

• Patent Grant
• 2154877

• References
• Source

• Patent Number

  2,154,877

• Date Filed

  Not available

• Date Issued

  Tuesday, April 18, 1939
  85 years ago

• CPC

  • B61L3/20 - employing different frequences or coded pulse groups

• US Classifications

  • 246 - Railway switches and signals