A steering gear frame includes upper and lower plates joined together at flange portions to define an inner space, a steering gearbox disposed to directly contact at least one of the upper and lower plates without using a bracket, and a fixing member for fixing the steering gearbox in a state where the steering gearbox is disposed to directly contact at least one of the upper and lower plates. The processor receives a trigger signal from the portable electronic apparatus when the portable electronic apparatus is in a standby mode. Two of the conductive pieces are electrically connected to an LED tube drive circuit board and the other two are connected to a fluorescent tube drive circuit board.