Lockout device for preventing telephone eavesdropping from an ex

Details Lockout device for preventing telephone eavesdropping from an ex Lockout device for preventing telephone eavesdropping from an ex

1996-05-23

1998-11-03

Kuntz, Curtis A.

Telephonic communications

Diagnostic testing, malfunction indication, or electrical...

For detection of eavesdropping device

379 35, 379167, 379168, 379185, 380 6, 380 8, H04M 124, H04M 308, H04M 322

Patent

active

058320571

ABSTRACT:
Remote telephone coder 10R and local telephone coder 10L provide coding and decoding for voice communication between remote telephone set 11R and local telephone set 11L through telephone line 12. An eavesdropper listening in on a listening device such as remote extension telephone 14R or local extension telephone 14L hears normal "in-the-clear" conversation (uncoded transmissions) when both of the telephone coders are in the normal mode. However, when both of telephone coders 10R and 10L are in the code mode, the extension eavesdropper using an extension telephone or other unauthorized listening device 14 (shown in phantom) hears only coded transmissions. Further, a remote eavesdropper on remote extension telephone set (main portion 17M with hand portion 17H) employing remote extension coder 16R is also excluded from the coded transmissions between remote telephone coder 10R and local telephone coder 10L.

REFERENCES:
patent: 4920565 (1990-04-01), Strawczynski et al.
patent: 4972469 (1990-11-01), Saltwick et al.
patent: 5210794 (1993-05-01), Brunsgard
patent: 5307370 (1994-04-01), Eness
patent: 5553126 (1996-09-01), Tang
patent: 5617476 (1997-04-01), Ibaraki et al.

Affiliated with

Also associated with

Rating

Lockout device for preventing telephone eavesdropping from an ex does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Lockout device for preventing telephone eavesdropping from an ex, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lockout device for preventing telephone eavesdropping from an ex will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-698821