PURPOSE: To charge a portable radio machine having no chargers like an AC power source or a DC power source near it and to operate the portable radio machine as a changeover switch by providing a means by which it can be charged from the solar battery set to a collapsible open/close cover.

CONSTITUTION: A chargeable charging battery 2 is attached to a main body 3, and an open/close cover 1 is attached by such structure that it can be opened and closed by a collapsible joint 4. The main body 3 is provided with a loudspeaker 5, a display part 6, operation keys 7, a microphone 8, etc., as a portable radio telephone set. A solar battery 9 is attached to the inside of the open/close cover 1. The charging battery 2 is charged by the solar battery 9 set to the collapsible open/close cover 1. The voltage change of the solar battery 9 according with the quantity of light for opening/closing of the open/close cover 1 is brought about by the setting position of the solar battery 9 to the open/close cover 1, and this machine can be operated as a changeover switch.