A method for producing submicron polytetrafluoroethylene powder in a free-flowing, readily dispersible form. When automatic stop conditions are satisfied, the engine 1 stops, and when restart conditions are satisfied, a starting motor 2 is started so as to restart an engine 1. Pipes can be protected from water corrosion, erosion and electrolysis, extending the life of pipes such as copper, steel, lead, brass, cast iron piping and composite materials. A channel compensation caused by a difference between a spreading factor of a pilot channel and a spreading factor of a data channel can be compensated on the condition that a slope compensator executed by a SF ratio is controlled by a filter coefficient controller.