| 摘要 |
PURPOSE:To flatten frequency characteristics of impedance by improving the attenuation of a trap by obtaining stepped group delay time characteristics on the whole by providing seed screen-shaped electrodes having characteristics leading and lagging flat characteristics of group delay time characteristics. CONSTITUTION:Reed screen-shaped electrodes are divided into two parts 19 and 20 and, in consequence, the logarithm of weighted reed screen-shaped electrodes is reduced. Elecrrode part 19 has characteristics leading flat characteristics of group delay time characteristics, and electrode parr 20 has lagging characteristics, so that stepped group delay characteristcs will be obtained on the whole. Thus, impedance frequency characteristics can be flattened by improving the attenation of a trap. |
