To avoid breaking and shorting troubles when a coaxial cable is connected to a board by using a dielectric-connected signal pattern film thicker than a ground pattern film connected to a shield.

A board 6 has a part at one end to which a coaxial cable 1 is connected, a connector 7 connected to a signal pattern through wires 10 is mounted on the other end, the body 2 of the cable 1 is connected to the board 6 to form a signal pattern 8 having a film thickness tS and ground pattern 9 connected to a shield 4 having a film thickness tG. The thickness difference between tS and tG agrees with the radius difference between the body 2 of the cable 1 and shield 4. Thus it is possible to prevent the deformation of the coaxial cable and avoid breaking and shorting troubles.