To prevent a substrate for mounting electronic components from being damaged when cores are rubbed together during assembly, a pair of core members sandwich a part of a coil pattern formed on the substrate from the top and bottom sides of the substrate, and the core members are held together by a core-combining member. The number of impeller blades of the front section impeller is more than that of the rear section impeller to reduce the noise generated during the rotation of the impeller. The metal base is made of stainless steel, and includes a frame structure having a first frame and a second frame. A photo-sensor is provided at the toss hoop to record a valid toss when a ball is tossed upwardly through the hoop within a predetermined height range and descends through the hoop prior to the serve. In this retardation film, the anchor layer is formed by applying an anchor material including a tri-, or more-functional acrylate monomer of 50 parts by weight or more and 90 parts by weight or less onto the thermoplastic norbornene resin film and then, drying and curing the anchor material with ultraviolet light.