BI-DIRECTIONAL AMPLIFIER FOR CATV

摘要

PROBLEM TO BE SOLVED: To realize bi-directional communication without cutting all incoming signals for preventing the inflow of merged noise to a center. SOLUTION: This bi-directional amplifier is provided with a variable filter 2 whose pass band is changed so that the frequency bands of merged noise can be cut, and the other bands can be transmitted when the amount of the merged noise in an incoming signal is increased in an incoming transmission line 1 and a variable control part 3 for changing the pass band of the variable filter 2 according to the amount of the merged noise in the incoming signal. Also, this amplifier is provided with an attenuator 4 arranged in the incoming transmission line 1 with the same attenuating level as that of the insertion loss of the variable filter 2 and a switching controlling part 5 for switching the passage of the incoming signal to the variable filter 2 or the attenuator 4 according to the amount of the merged noise in the incoming signal.