3689920

Information

• Patent Grant
• 3689920

• References
• Source

• Patent Number

  3,689,920

• Date Filed

  Not available

• Date Issued

  Tuesday, September 5, 1972
  52 years ago

• CPC

  • G08B29/02 - Monitoring continuously signalling or alarm systems
  • B64D2700/62219 - Electric safety devices

• US Classifications

  • 340 - Communications: electrical
  • 324 - Electricity: measuring and testing