| 摘要 |
An electronic circuit, for connecting a transmitter and receiver to a telephone line. The circuit operates on very low operating voltages from the line which allows parallel operation with a conventional set on long-loop applications. In its functional form, the circuit utilizes a bridge configuration having transistors in two of its legs, driven by the transmitter output, thereby eliminating the usual bridge balancing resistors therefrom and their concomitant operating voltage drops thereacross. |
