Abstract: To obtain a receiver circuit unit for radio controlled toys configured such that the drive of a plurality of types of radio controlled toys can be controlled by a single transmitter by removably mounting the receiver circuit unit as a separate item. To provide a receiver circuit unit for radio controlled toys configured such that a receiver circuit unit mounting portion is provided in each of a plurality of types of radio controlled toys containing a drive mechanism, and a single receiver circuit unit is interchangeably and removably mounted on the receiver circuit unit mounting portion, whereby the drive of the plurality of types of radio controlled toys can be controlled by a single transmitter.

Abstract: A swimming element enjoying system capable of applying an external stimulus to a swimming element moved at a predetermined rhythm, to thereby permit the swimming element to carry out different motion, to thereby provide an observer with a fresh surprise, so that the observer may be soothed or healed. A swimming element made in imitation of an aquatic life and a drive unit for driving the swimming element each are provided with a permanent magnet. The permanent magnet of the drive unit is rotated, to thereby permit an attracting/repulsing action to be carried out between the permanent magnets, leading to random vertical motion of said swimming element. Motion of the swimming element is randomly varied when a sensor detects an external stimulus.