Telephonic communications – Supervisory or control line signaling – Using line or loop condition detection
Patent
1984-09-27
1986-12-23
Rubinson, Gene Z.
Telephonic communications
Supervisory or control line signaling
Using line or loop condition detection
H04M 322
Patent
active
046313621
ABSTRACT:
An origination scan circuit for detecting circuit closure state in a loop circuit has a much lower impedance than does the typical loop circuit. Its source impedance is split into separate resistive parts for connecting opposite terminals of an office battery to the tip and ring leads of the loop. Currents in the separate resistive parts are sensed and summed for comparison against a threshold current to indicate whether or not a subscriber station on the loop is off hook. Threshold current magnitude is variable to accommodate loop start and ground start applications. When the off-hook state is detected, the origination scan circuit is disabled by switching open the resistive part connections, and loop current is thereafter provided by other suitable means. Automatic current limiting arrangements are included for converting the switching functions to high impedance circuit elements.
REFERENCES:
patent: 3855420 (1974-12-01), Steidl
patent: 4099032 (1978-07-01), Roge et al.
patent: 4115664 (1978-09-01), Laface et al.
patent: 4319093 (1982-03-01), Bars
patent: 4320260 (1982-03-01), Lechner
patent: 4322586 (1982-03-01), Mein et al.
patent: 4358645 (1982-11-01), Brown
patent: 4360709 (1982-11-01), Hamazato et al.
patent: 4385336 (1983-05-01), Takeshita et al.
patent: 4406929 (1983-09-01), Pace et al.
patent: 4419542 (1983-12-01), Embree et al.
patent: 4451703 (1984-05-01), Brightman et al.
patent: 4454477 (1984-06-01), Joffe
patent: 4563547 (1986-01-01), Booth
Arntsen Tom D.
Embree Milton L.
Havens Joseph H.
Toumani Rouben
AT&T Bell Laboratories
Phelan Charles Scott
Rubinson Gene Z.
Vaas R.
LandOfFree
Low resistance origination scan circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Low resistance origination scan circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Low resistance origination scan circuit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-172549