| 摘要 |
A beam current limiter for a kinescope of a television receiver includes a control transistor, sensing means for providing a control voltage representative of the magnitude of beam current and a clamping network coupled to the sensing means. When beam current is below a predetermined value, the control voltage is clamped to a fixed level such that the transistor is in a first (e.g., non-conductive) condition. When beam current exceeds the predetermined value, the clamping network is disabled and the transistor conducts in response to the control voltage to provide an output signal related to the amount by which the predetermined value is exceeded. In one embodiment of the invention, the output signal is supplied to a second or black level clamping circuit associated with a video amplifier to translate a black or blanking level of a video signal in a direction for causing the kinescope to conduct less beam current.
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