A metal pattern for a high frequency signal is patterned on a flexile substrate, and the flexile substrate is bent in such a way as to form a substantially right angle at a spot corresponding to an end of the metal pattern for the signal. And an end of the metal pattern is fixedly attached to a lead pin for signaling, attached to a stem, for electrical continuity, so as to be in a posture horizontal with each other. Meanwhile, a part of the lead pins attached to the stem, being in such a state as penetrated through respective holes provided in the flexible substrate, is fixedly attached to a part of metal patterns provided on the flexible substrate so as to ensure electrical continuity therebetween.