Patent
1980-09-09
1982-03-16
Robinson, Thomas A.
H04Q 300, H04M 322
Patent
active
043202608
ABSTRACT:
A circuit arrangement for determining the connection condition of a plurality of subscriber lines in a telecommunication network, each of the subscriber lines having two wires extending between a subscriber station and a subscriber line interface circuit and being connected via respective resistors to the two poles of a DC voltage source. For a group of such subscriber lines the operating conditions are consecutively monitored by sampling the voltage occurring at two sampling points of both wires by a respective multiplexor and passing it to a comparator having inputs which are temporarily inter-connected by filter capacitors each separately associated with a respective subscriber line interface circuit. In addition, the comparator receives a reference voltage determining a threshold voltage. For ground key indication one of the sampling points is connected to one input of a further comparator which second input is supplied by a corresponding further reference voltage. The output signals of both comparators are presented at a central control unit for evaluation. When monitoring a ground key indication the output signal of the second comparator, however, is passed only if presupposed signals indicating correct operation, i.e. closed loop condition are present.
Robinson Thomas A.
Siemens Aktiengesellschaft
LandOfFree
Circuit arrangement for determining the connection condition of does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Circuit arrangement for determining the connection condition of , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuit arrangement for determining the connection condition of will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1642913