| 摘要 |
This invention is a circuit for reducing the power requirements for a subscriber's line where the loop length is short. The circuit senses the line current in the off-hook condition, and if the line current is above a predetermined threshold, it decreases the power supply voltage. When the line is restored to the on-hook condition, the original high voltage is restored. A substantial reduction in the cost and size of the power supply is thus obtained. |
