| 摘要 |
PROBLEM TO BE SOLVED: To easily adjust the vertical size of the display screen of a CRT while attaining cost reduction. SOLUTION: When the vertical size of the display screen of a CRT 50 is inputted through a remote controller 60, a control voltage E at a level corresponding to these data is outputted from a microcomputer 10. Since this control voltage E is supplied to an amplitude variable circuit 30 for amplifying a vertical synchronizing signal B as a power supply voltage, the amplitude of the vertical synchronizing signal B outputted from the amplitude variable circuit 30 is changed. A control current F corresponding to the level of the vertical synchronizing signal B is generated by a control current generating circuit 80. A vertical deflection IC 40 generates a saw-tooth wave signal C synchronized with the vertical synchronizing signal B and has a function not only for outputting it to a vertical yoke coil 51 of the CRT 50 but also changing the peak value of the saw-tooth wave signal C corresponding to the control current F. Therefore, the vertical size of the display screen of the CRT 50 is adjusted corresponding to setting input. |
