| 摘要 |
PURPOSE:To improve the cutoff performance at the high frequency side, by insulating an end of each of >=2 parallel resonators consisting of coils and capacitors froem a shielding case to connect them to each other and opening the other end respectively. CONSTITUTION:A shielding case 8 contains 4 rooms 11 and 12, and the rooms 11 at both ends of the case 8 include the parallel resonators 15 and 15' with the capacitors 14 and 14' connected to both ends of the coils 13 and 13', and an input winding 16 and an output winding 17 with an end connected to the case 8 and the other end insulated from the case and then drawn outside respectively. A coupling window 18 is formed to a partition wall 9 between the room 11 and the center room 12, and the parallel resonators 21 and 21' consisting of the coils 19, 19' and the capacitors 20, 20' connected to both ends of the coils 19 and 19' are disposed in the room 12. As no window is provided to a partition wall 10 of the room 12, the resonators 21 and 21' are separated from each other in terms of the electric field. Then an end of each of the resonators 21 and 21' is connected to each other to have an electromagnetic connection. The other end of each of the resonators 21 and 21' is opened, and a trap circuit is formed for connection of capacity by means of the capacity between the resonators 21/21' and the case 8. |
