| 摘要 |
PURPOSE:To prevent a horizontal output transistor (TR) and a horizontal oscillating circuit from breaking down, by holding oscillation at a higher oscillation frequency corresponding to a higher horizontal scanning frequency while a current is detected by a current detecting circuit. CONSTITUTION:When a signal from the current detecting circuit 11 is applied to the base of the TR17 through a base resistance 16, an oscillation frequency switching circuit 13 turns on the TR17 to makes a parallel connection between capacitors 19 and 20 for determining an oscillation frequency, deciding on a lower oscillation frequency as the oscillation frequency of the horizontal oscillating circuit 1. When a low-level signal is applied to the base of the TR17 through the resistance 16, the TR17 is turned off to connect only the capacitor 20 for deciding on the oscillation frequency, and consequently the higher oscillation frequency is determined as the oscillation frequency of the circuit 1. |
