To reduce costs by abandoning the resin of an L type probe, and to reduce a manufacturing process by connecting the L type probe to a substrate by reflow soldering.

This L type probe 3 is provided with a disc-shaped downward detent 8 and a plate-shaped rotational movement stop 9 at the upper edge part. Then, a probe insertion hole 10 of a substrate 1 on which the L type probe 3 is to be mounted is shaped like a key hole, and the diameter of the circular part is set so as to be smaller than that of the disc-shaped downward detent 8 of the L type probe 3 so that the plate-shaped rotational movement stop 9 can be engaged with a rectangular hole part following the circular part. When the L type probe 3 is inserted through the probe insertion hole 10 formed at the substrate 1 and the probe insertion hole 11 of a chassis 7, the L type probe 3 is fixed on the substrate 1 by preventing the L type probe 3 from being moved in the vertical direction or in the rotational direction. Thus, it is possible to abandon a resin layer converting the L type probe 3 for insulation.