A novel Doherty amplifier with improved efficiency is disclosed. or higher for a certain period of time, and then removing precipitate generated by the heating from the nickel-electroplating solution together with the added rare earth compound by sedimentation andor filtration. In another form, the floatation aid is incorporated in pants or other article of clothing being located in a pocket and secured to the pants or article of clothing. They may define different security policies for different types of transactions. A synchronization signal may be transmitted using the identified synchronization frame and the selected slot.