| 摘要 |
A method and apparatus for adjustment of the white balance of a CRT display system enabling white balance adjustment to be performed in a short time and a television receiver using the same. The white balance adjustment apparatus has a level adjustment circuit, an attenuation resistor, a video signal output circuit, a coupling capacitor, and a synchronous-signal-tip level clamp circuit and is connected to the cathode electrode. The level adjustment circuit has a variable amplifier which amplifies only the video signal component V, a synchronous signal separation circuit, a variable amplifier for causing attenuation of the horizontal synchronous signal H-SYNC, a signal addition circuit, and an AND gate. In the white balance adjustment mode, the ratio of levels of the video signal and synchronous signal is changed from the usual 0.714:0.218 to, for example, 0.714:0.005. By this, even when the drive voltage is adjusted in the synchronous-signal-tip level clamp circuit after the adjustment of the background in the level adjustment circuit, there is less change of the horizontal synchronous signal and there are, therefore, less number of tracking operations needed between the adjustment of the background and the adjustment of the drive voltage.
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