Abstract: A pulse generating device generates an output pulse by controlling the amplitude of a triangular wave at a constant level by use of an AGC circuit and wave-shaping the triangular wave when the triangular wave is generated by triggering a monostable multivibrator circuit by an input pulse, driving an integrating circuit having substantially the constant charging/discharging ratio by an output of the monostable multivibrator circuit, and controlling a current source which supplies a current to the integrating circuit according to an output of comparison between the integrated output and a reference voltage.

Abstract: A television receiver includes a first signal processing unit that generates contrast controlled first R, G and B signals and a second signal processing unit that outputs second on-screen R, G and B signals. A switching unit receives the first and second R, G and B signals and selectively outputs one of them to a color CRT. An ABL voltage, which changes in response to a level of video displayed on the CRT, is provided to the first and the second R, G and B signals. A control unit determines whether to execute the contrast control of the second R, G and B signals based on a ratio of video corresponding to the second R, G and B signals out of the total video displayed on the color CRT.