Key system protective apparatus

Details Key system protective apparatus Key system protective apparatus

H - Electricity

04

M

317/11, 379/33,

H04M 3/42 (2006.01) H04M 9/00 (2006.01)

Patent

CA 1139469

KEY SYSTEM PROTECTIVE APPARATUS ABSTRACT OF THE DISCLOSURE: A circuit for apparatus to be used with a key system line card for providing electrical isolation between the line circuit and the station instrument. The adapter responds to ring current from the central office to close a path to the line circuit to cause the line circuit to respond. The circuit provides two-way supervision responding to change of conditions either at the station or at- the central office, and also provides a time delay to prevent the circuit from entering the hold condition improperly.

340431

Affiliated with

Also associated with

Rating

Key system protective apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Key system protective apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Key system protective apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-779801