| 摘要 |
PURPOSE:To secure the duplex property only for the signal of a specific property and then the directional property for the TV signal respectively, by connecting two units of the specific frequency duplex property generating elements to the branching element. CONSTITUTION:The sides (e) and (f) of the branching element 11 having a directional property are connected to the input and output terminals 8 and 9, and the side (g) is connected to the side (j) of the duplex property generating element 13. On the other hand, the specific frequency duplex property generating element 12 functions to block only the signal having a specific frequency. The side (h) of the element 12 is connected to the terminal 9, and the side (f) is connected to the branch terminal 10 along with the side (k). In such constitution, the signal loss quantity of the terminal 10 is low over a wide frequency range in case when the signal is supplied through the terminal 8, and the signal loss of the terminal 10 is low only at the characteristic frequency band in case when the signal is supplied through the terminal 9 respectively. As a result, the duplex property is secured for only the signal of communication frequency of a carrier-type interphone or the like, and the directional property is secured for the TV signal respectively. Thus the TV common receiving facilities can be shared as a communication circuit. |
