| 摘要 |
PURPOSE:To reduce the loss of a communication circuit and at the same time eliminate a bad influence to the TV picture quality, by giving a directivity to the signal of the TV broadcast and a double directivity to the signal of the frequency band of a cairrer-type interphone or the like. CONSTITUTION:The sides (a) and (b) of the primary winding L1 of the coupling transformer T1 are connected to the input terminal 8 and the output terminal 9. The side (c) of the secondary winding L2 is earthed with the side (d) connected to the branch terminal 10. On the other hand, the side (e) of the primary winding L3 of the coupling transformer T2 is connected to the terminal 8 with the side (f) earthed. The side (h) of the secondary winding L4 is connected to the terminal 10 with the side (g) earthed via a parallel resonance circuit and a resistance. |
