| 摘要 |
PURPOSE:To easily adjust a circuit to an optimum value by providing a second micro strip line having a preliminarily determined shape where an impedance adjusting element is formed on the dielectric having a second dielectric constant lower than a first dielectric constant. CONSTITUTION:An adjustment part 8 is provided with a substrate 81 using a dielectric of, for example, Teflon (epsilonr=2 to 3) whose dielectric constant is lower than the dielectric constant (epsilonr=8 to 10) of a substrate 3 and a ladder part 82 which has bars (d), (e), and (f) for adjustment formed as micro strip lines on the substrate 81. The substrate 81 is adhered to Line substrate by an adhesive or the like, and the ladder part 82 is connected to micro strip lines 6 by soldering. Since the dielectric constant of the substrate 81 is 1/3 to 1/5 of that of the substrate of the base, the electric length of the ladder part 82 is 1/3<1/2> to 1/5<1/2> of that of the adjustment part on the substrate though micro strip lines on these substrates have the same physical length. Consequently, the electric length is changed by about 1/2 step, and fine adjustment is possible. |
