Adjustable impedance battery feed circuit

Details Adjustable impedance battery feed circuit Adjustable impedance battery feed circuit

1978-03-24

1979-11-27

Claffy, Kathleen H.

179 70, H04M 176, H04M 1900

Patent

active

041762550

ABSTRACT:
The magnitude of current supplied to a subscriber telephone loop during both loop start and ground start modes of operation is controllably limited by employing a battery feed circuit including an adjustable line build-out impedance. Resistors are controllably switched in or out of the battery feed circuit leads as a function of the potential developed across the line build-out impedance in a predetermined one of the battery feed circuit leads. Since the line build-out impedance being adjusted in value is within the detection loop, there is hysteresis in the switch points for switching the resistors in and out of the battery feed circuit leads. This hysteresis minimizes possible oscillation at the switch points and, therefore, minimizes development of unwanted signals on the subscriber loop. The use of an adjustable line build-out impedance further allows use of small resistance value, low wattage resistors as line build-out impedance elements. This improves overall efficiency and allows use of longer subscriber loops.

REFERENCES:
patent: 3035122 (1962-05-01), Livingstone
patent: 3187104 (1965-06-01), Ebel

Affiliated with

Also associated with

Rating

Adjustable impedance battery feed 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 Adjustable impedance battery feed circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adjustable impedance battery feed circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-803734