1930921

Information

• Patent Grant
• 1930921

• References
• Source

• Patent Number

  1,930,921

• Date Filed

  Not available

• Date Issued

  Tuesday, October 17, 1933
  91 years ago

• CPC

  • H04Q5/20 - the subordinate centre permitting interconnection of subscribers connected thereto

• US Classifications

  • 379 - Telephonic communications