| 摘要 |
<p>12.2.1980 1 PHN 9451 Line circuit. A line circuit comprising a terminal for connection of a wire of a subscriber's line for applying thereto a line current which is determined by the impedance of the subscriber's line and an alternating current which is superimposed on the line current, the circuit further comprising an amplifier and a current injection circuit connected to the output of the amplifier for supplying a portion of the line current, determined by the impedance of the current injection circuit, the amplifier supplying the remaining portion of the line current.</p> |
