The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 12, 1982
Filed:
Jun. 24, 1980
Donald A Chandler, Reno, NV (US);
John W Harper, Sparks, NV (US);
S.I.C., Inc., Havertown, PA (US);
Abstract
A portable field unit for conducting and controlling emergency telephone communications, particularly in hostage situations, is disclosed. Three telephone lines and a monitoring line can be connected to the unit, which can function as a miniature manually operated central office. A prime operator can control a first line and a common line, while a backup operator can control a second line and the common line. The backup operator can monitor the prime operator's line, and the prime operator's line can also be remotely monitored. The first line and the common line can be patched together by the prime operator for direct communication between them. A privacy switch is provided under the prime operator's control to produce a masking tone in the monitoring circuits when a private communication between the first line and the common line is desired.