| 摘要 |
<p>A line powered electronic network which utilizes a bridge configuration for connecting a microphone and receiver to a telephone line which provides increased line voltage during operation of an associated tone generator. The network is so constructed that the d-c voltage across the line is increased during operation of the associated tone generator so as to prevent clipping of the tone signals. Each of the d-c feedback paths around the amplifier of the network includes a plurality of R-C networks connected in cascade so as to provide sufficient filtering at low audio frequencies while meeting the overall time constant required for changing the d-c operating conditions of the set.</p> |
