A recreational or competitive flying disc includes an illumination system employing an array of flexible optical fibers to distribute the light of a single light emitting diode from the rotational center of the disc to its outside periphery. In one embodiment, one or more propagation effects are estimated by using a phase comparison between an upper sideband and a lower sideband of a satellite navigation signal. Each base station communicates with mobile stations up to several miles away. Upon reception of the window size, the terminal device magnifies the sharing-selected window screen according to the received window size. The rear bottom extends in a peripheral wall projecting outwardly away from the frame wall and in substantial alignment therewith, to the free edge of said peripheral wall a cover being applied to delimit a chamber adapted to receive electric elements complementary to the motor.