| 摘要 |
The terminal station (1) is used for supply feed, and data transmission are two-way. It contains two amplifiers (11,17) for the two transmission directions, and between the output of the first (11) and coaxial cables with tubes (3,6), a high pass filter (12) is connected. A similar filter (16) is likewise incorporated in the opposite direction. To the inner conductors of the coaxial tubes on the output from the station, poles on a constant power set (14) are connected via two low pass filters (13,15). A series of repeaters (2) are used, with high frequency signals passing from the coaxial tube (3) through them via a high pass filter (21), an amplifier (22) and a further high pass filter (23) on to the next coaxial tube in the direction of transmission. The repeater circuit is fed with direct current via a low pass filter (24) a zener diode (DZ1) and yet another low pass filter (25) so that the high frequency path through the repeater is shunted. (Provisional Basic advised week E05) |
