Telephone line lifting apparatus

Details Telephone line lifting apparatus Telephone line lifting apparatus

1977-07-27

1978-11-21

Olms, Douglas W.

Deposit and collection receptacles

Fare boxes

Multiple coin slot and runway

179 2A, H04B 346

Patent

active

041267710

ABSTRACT:
A line lifting apparatus is disclosed which functions to connect and disconnect a customer station and a telephone line extending from a central office to the customer station, for line testing purposes. The connection and disconnection is provided by a bistable latching relay which is controlled by a control circuit responsive to potentials impressed on the conductors of the telephone line. A first potential applied to either or both of the conductors of the telephone line causes the control circuit to place the bistable latching relay in a state wherein the telephone line is disconnected from the customer station, and a second potential applied to either or both of the conductors of the telephone line causes the control circuit to place the bistable latching relay in a state wherein the telephone line is connected with the customer station. The second potential differs in either magnitude or polarity from the first potential and preferably has a magnitude substantially equal to that normally applied to the telephone line at the central office by the central office station battery, and a like polarity, so that connection between the telephone line and the customer station is assured in normal operation of the telephone system. Four specific embodiments of the control circuit are disclosed, as is an embodiment of a switchable power supply adapted to selectively provide the first and second potentials at the central office.

REFERENCES:
patent: 3725613 (1973-04-01), Allen et al.
patent: 3739107 (1973-06-01), Spencer
patent: 3773986 (1973-11-01), Tremblay
patent: 3852537 (1974-12-01), Vincent
patent: 3867588 (1975-02-01), Pickens et al.
patent: 3919487 (1975-11-01), Gabrielson
Del-Tronics Associates, Inc., Model DTA-103, Jan. 16, 1976.

Affiliated with

Also associated with

Rating

Telephone line lifting 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 Telephone line lifting apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Telephone line lifting apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2050415