| 摘要 |
When amplitude-modulated signals are received, pulse-shaped interference of different types becomes increasingly noticeable, particularly in the case of long-distance reception, which can completely prevent the reception of such transmissions. A noise gating device is therefore required which constantly operates well independently of the input signal level and the type of noise pulses. For this purpose, the mean signal level is kept constant by picking up the actual value of the controlled variable after the gating out of the noise signal and the gating pulses generated by a dual comparator being passed via a high-pass filter before they affect the gating out. To enhance the effectiveness of the noise gating, particularly in the case of higher noise pulse frequencies, the actual value of the controlled variable can be conducted via a band-pass filter before it reaches the comparator.
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