| 摘要 |
PURPOSE:To select optionally an input coupling degree and to facilitate easy design and control of a tuner by constituting a cavity resonator with a double cavity and ensuring easily the tuning in a wide range of bands with the double cavity. CONSTITUTION:A cavity resonator is formed with an inside cavity 6 formed between a center conductor 4 and a cylindrical intermediate conductor 5 and an outside cavity 8 formed between the conductor 5 and a cylindrical external conductor 7. These cavities 6 and 8 are terminated by short circuit plates 9 and 10 respectively. The plates 9 and 10 can be moved independently of each other toward the axial direction of this double cavity for control of input impedance of both cavities 6 and 8. Furthermore both cavities 6 and 8 share the conductor 5, and the impedances of both cavities are connected in series via the conductor 5. Thus the input coupling degree can be selected optionally for this cavity resonator, and therefore both design and control are facilitated for a tuner. |
