| 摘要 |
PURPOSE:To prevent an unnecessary current from being flowed to a degaussing coil after the completion of degaussing, by providing a charging circuit which is charged when a power supply switch turns on and connecting a series circuit consisting of the degaussing coil and a relay contact between the output terminal of this charging circuit and the earth. CONSTITUTION:When a power supply switch turns on, a pulse is generated in the secondary winding of a fly-back transformer 1 and is rectified by a rectifying circuit 2 to charge a capacitor 3b of a charging circuit 3. The voltage of a capacitor 16 rises simultaneously with making of the power supply switch, and a transistor (TR) 12 is conducts after the elapse of a certain time, and as the result, a TR 10 is cut off. Then a current is flowed to a TR 7 through a capacitor 9 for a short time to make the TR 7 conductive. As the result, a current is flowed to a relay 4 for a short time to close the contact, and a damping oscillating current is flowed to a degaussing coil 5, and thus, degaussing is completed before rasters appear on the picture screen. |
