A mobile wireless communications device may include a portable housing and a printed circuit board carried by the portable housing. The assembly includes a first frame member having a first plurality of tabs extending away from a first peripheral edge of the first frame member. It is also possible for a lyophilic surface to be formed on the surface of the groove portion between the first partition wall and second partition wall. The handle, venture, and baffle are all one piece. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 3 so as to be collided with the circumferential surface 53 of the cooling roll 5, so that the molten alloy 6 is cooled and then solidified. The absence of a VCO within the direct frequency synthesizer, provides the direct frequency synthesizer with lower phase noise than a typical PLL-based coarse step synthesizer.