Folded circuit of two-wire carrier line by group

Abstract

Abstract PURPOSE:To constitute a folded line by designating an optional repeater or an opposite side terminal station from one terminal station device, driving a frequency converting means and a changeover switch and applying connection from a low group to a high group to attain the test of a folded carrier wave line from a terminal station. CONSTITUTION:A directional filter 2 separating a low group signal from a cable line L is provided to each repeater or a terminal station device of a 2-line carrier line by group, the separated low group signal is amplified by a low group line amplifier 4 and transmitted to a cable line L' from a directional filter 2'. Further, a high group signal from the line L' is transmitted to the line L via the filter 2', a high group line amplifier 3 and the filter 2. Further, the output of the amplifier 4 is branched by a BPF6 passing the output of the amplifier 4 at a low frequency band and inputted to a modulator 8, a spurious wave is eliminated an LPF9 to change over a changeover switch 10. Further, a specific frequency is fed to the filter 2 from a test measuring device T via a low group amplifier 1 to attain the folded test of the carrier wave line.

Inventors

• 👤 Masao Kodama
• 👤 児玉　正夫
• 👤 Osamu Nakamura
• 👤 修 中村

Bibliographic Details