| 摘要 |
PURPOSE:To cause a horizontal deflecting width to be variable without inviting heating due to the large current of a horizontal deflecting coil by providing a means to switch the value of a resonance capacitor, which is parallelly connected with the horizontal deflecting coil of a deflection yoke. CONSTITUTION:Capacitors 21 and 22 to be serially connected constitute a resonance capacitor 5 of a horizontal deflecting coil 3. Since the transistor of a photo-coupler 26 is turned on in a condition that a switch 28 is closed, a semiconductor 23 goes to a turning-off condition and the capacitors 21 and 22 go to a serial condition for the resonance capacitor 5. Since the transistor of the photo-coupler 26 is turned off when the switch 28 is opened, the semiconductor element 23 goes to a turning-on condition. Then, since the resonance capacitor 22 goes to a short-circuit condition, the resonance capacitor 5 of the horizontal deflecting coil 3 is only the capacitor 21. |
