| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that the level of noise reaching a center increases when the noise input is hardly made from a subscriber terminal, etc., connected to a tap-off with small loss installed at a distance from a repeating amplifier although a CATV system transmission line has large loss to an incoming signal and the noise from the subscriber terminal is hardly inputted since the branch loss and insertion loss of the tap-off are so designed that the level of an outgoing signal is equal at each subscriber terminal and then the branch loss is set large for a tap-off close to the repeating amplifier. SOLUTION: At a tap-off arranged at a specific position on a tap-off line, an attenuator is arranged in an incoming transmission line arranged between two directional filters and incoming mixed noise is reduced without affecting the outgoing signal. |
