| 摘要 |
PURPOSE:To use a transfer switch without increasing noise by connecting one end of a discharge lamp to the position with no high-frequency potential via an element with low impedance to high frequencies when the lighting state of the discharge lamp is changed by the transfer switch. CONSTITUTION:When contact points of a transfer switch 21 are located at 201, 205, both discharge lamps 7, 8 are lit. Since a capacitor 19 is short-circuited with the contact points 201, 205 at this time, it gives no effect to the lighting of the discharge lamps 7, 8. When the contact points are moved to 202, 206, the contact point 205 is opened, thus only the discharge lamp 7 is lit, and the discharge lamp 8 is connected to an AC power supply 1 via a capacitor 19. The value of the capacitor 19 is such that the discharge of the discharge lamp 8 can not be maintained. When the discharge lamp 8 is not lit, the other end is not opened. The antenna operation is thereby reduced, and the increase of noise can be prevented. |
