| 摘要 |
A method and apparatus for amplifying television picture signals. The amplified television picture signals from an amplifier are monitored by a circuit arrangement including a Zener diode. When the amplitude level of the amplified signals exceeds a predetermined value, the Zener diode becomes conductive and an auxiliary signal is generated. A normally high resistance semi-conductor arrangement is connected in parallel with the high resistance in the input circuit of the amplifier. The semi-conductor arrangement is normally non-conductive, and in such cases, the effective load impedance at the input of the amplifier is substantially equal to the high resistance. When the auxiliary signals are applied to the semi-conductor arrangement, the latter becomes conductive to thereby provide a substantially lower resistance in the input circuit of the amplifier. In the latter case, the voltage levels developed at the input of the amplifier are limited, to thereby limit the amplitude of the amplified signals at the output of the amplifier.
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