PURPOSE: To improve the impedance matching performance and the circuit characteristic by configuring conductive frame body as an almumost half-column around a conductive pin.

CONSTITUTION: A half-columnar structure is secured for a frame body D set around a conductor pin B serving as a vertical converting part of a strip line C, and the line C is set in the body D. Then an almost coaxial line structure is secured for the semicircular parts of both pin B and body D and therefore the electric force lines have an almost even distribution. Furthermore the specific impedance Zo is defined in the coaxial line structure as Zo=138/√elog102ro/a, where ro shows the radius of the half-columnar part of the body D. When Zo=50Ω, a=1.3mm, and e=2.2 are substituted for the preceding equation, ro=2.3mm is satisfied. The structural condition is defined as ro=0.5a and therefore this condition is satisfied. Therefore the specific impedance of 50Ω is attained by the half-columnar structure of the body D. Thus it is possible to estimate a specific impedance and to ensure the satisfactory impedance matching performance and also the satisfactory circuit characteristic.