HP HP 54600B, Руководство пользователя и сервисное руководство

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To reduce the random noise on a signal
If the signal you are applying to the oscilloscope is noisy (figure 2-21), you
can set up the oscilloscope to reduce the noise on the waveform (figure
2-22). First, you stabilize the displayed waveform by removing the noise
from the trigger path. Second, you reduce the noise on the displayed
waveform.
1
Connect a signal to the oscilloscope and obtain a stable display.
2
Remove the noise from the trigger path by turning on either high
frequency reject or noise reject.
High frequency reject (HF reject) adds a low pass filter with the 3 dB point at
50 kHz (see figure 2-19). You use HF reject to remove high frequency noise
such as AM or FM broadcast stations from the trigger path.
HF reject
3 dB down point
Pass
Band
dc
0 dB
50 kHz
Figure 2–19
Operating Your Oscilloscope
To reduce the random noise on a signal
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