| 摘要 |
A wide-band transistorized amplifier including between two line couplers a cascade of stages of amplification and a negative feed-back quadripole connecting the output from the last stage of the cascade to the input to the first, and including a stage of correction by forward gain control, which is arranged in parallel across one of the stages of the cascade, which is connected to one of the couplers, characterized by the fact that the stage (10, 12) of the cascade, across which the correction stage is arranged in parallel, introduces a phase reversal, and that the correction stage includes a CE transistor (20, 20', 20'') the base of which is connected on the one hand through an inductive phase-shift impedance (19, 19', 19'') to the input to the said stage (10, 12) of the cascade, and on the other hand through a resistor (23, 23', 23'') to the output from the said stage of the cascade, and the collector of which is connected through the putting in parallel of a resistor (21, 21', 21'') and a capacitor (22, 22', 22'') to the output from the said stage of the cascade, so that the wanted signal is substantially cancelled at the input to the transistor of the correction stage, and that the noises generated by the said stage of the cascade, which are amplified by this correction stage, are substantially reduced at the level of a load (5) connected to the output from the amplifier.
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