| 摘要 |
1. A line amplifier, in particular for carrier frequency or high frequency transmission paths, comprising a circuit arrangement for coarse surge voltage protection at the input end and output end from excess voltage interference, and comprising current supply branches (2, 4 ; 9, 11) for the remote supply of the line amplifier via the cable inner conductor of the transmission path, wherein the input (E) and the output (A) of the line amplifier are d.c. coupled together via low-pass filters (2, 11) of the current supply branches (2, 4 ; 9, 11) and the d.c. connections decoupled to a cable outer conductor (13) by means of a capacitor (3, 12) at least at one point, and in particular comprising the arrangement of a choke (10) for the d.c. connection of the low-pass filters (2, 11) and decoupling of the low-pass filters (2, 11) to the cable outer conductor connection (13) on each side of the choke (10) by means of a separate capacitor (3, 12), characterized in that at least one surge voltage arrester (1) is arranged only at the input (E) of the line amplifier for coarse surge voltage protection of the input end and output end, and that the chokes (2, 11) of the current supply branches (2, 4 ; 9, 11) and further chokes (10) which are possibility arranged in the d.c. connection path between input (E) and output (A) are so designed and dimensioned that they are saturated by surge currents with slow flanks, and that the d.c. connection between the input (E) and the output (A) of the line amplifier is designed and/or wired in such manner that the voltage drop thereon is limited. |
