1742639

Information

• Patent Grant
• 1742639

• References
• Source

• Patent Number

  1,742,639

• Date Filed

  Not available

• Date Issued

  Tuesday, January 7, 1930
  95 years ago

• CPC

  • H01B11/143 - using helically wound magnetic tape

• US Classifications

  • 178 - Telegraphy
  • 156 - Adhesive bonding and miscellaneous chemical manufacture
  • 174 - Electricity: conductors and insulators