摘要 |
<p>A circuit closes a remote feed loop of a series-supplied repeater in a communications channel, in the event of an interruption in the transmission line, by means of a relay which senses an interruption in the feed current to close a shunt circuit. The shunt circuit includes a resistance which is initially high, to promote rapid restoration of the communications circuit, and afterwards is lowered to minimize losses and to promote personal safety.</p> |