3685009

Information

• Patent Grant
• 3685009

• References
• Source

• Patent Number

  3,685,009

• Date Filed

  Not available

• Date Issued

  Tuesday, August 15, 1972
  52 years ago

• CPC

  • G01V1/001 - Acoustic presence detection
  • H03G9/10 - for tone control and volume expansion or compression
  • Y10S367/901 - Noise or unwanted signal reduction in nonseismic receiving system

• US Classifications

  • 367 - Communications, electrical: acoustic wave systems and devices