A functional timepiece module is integratable in a mechanical modular unit, and the functional module is derived from a sub-assembly carrying components for a particular timepiece function of transferring a movement between input and output wheel sets. The technique involves reducing the amount of time that a receiver is powered-up during a time interval that the radio communication device may receive a transmission from another radio communication device. The flat portion has a plurality of slots formed therein and is divided into several sections by the slots. The opening and closing cam followers and valve are all collinear when viewed from the end of the cam shaft.