| 摘要 |
PURPOSE:To turn ON a power source by operating means for other function by providing automatic power source control means connected to a battery power source and receiving outputs of operating means and normal/reverse direction detecting means to supply a battery power source voltage to circuits in an electronic apparatus. CONSTITUTION:When a knob of a rotary encoder 1a is rotated, an output pulse of a brush of a commutator 1a' generates a pulse train. The output of FF2 becomes an 'H' level by the pulse of the H level of the pulse train. As a result, a transistor Tr1 is turned ON by the base bias of the transistor Tr1, the base of a transistor Tr2 becomes an 'L' level, and a power source voltage Vcc is supplied to power source circuits of electronic apparatus from the cell 2 of the power source through the transistor Tr2. |
