The invention provides a printed circuit board including a first surface, a second surface which is a rear surface to the first surface, a connector installed on the first surface, and, formed between the first surface and the second surface, one of a through hole piercing the printed circuit board and a recess formed in an edge section of the printed circuit board; a cable including a first terminal that is removably fitted to the connector and a connecting wire portion located between the first terminal and a second terminal, the connecting wire portion extending from the first surface to the second surface of the printed circuit board through the one of the through hole and the recess when the first terminal is in a state of being fitted to the connector; and a casing for containing the printed circuit board and the cable.