Low-frequency reject (LF reject) adds a high-pass filter with the 3-dB point at
50 kHz. Use LF reject to remove low-frequency signals, such as power line noise,
from the trigger path.
0 dB
3 dB down point
dc
LF Reject
Noise reject increases the trigger hysteresis band. By increasing the trigger
hysteresis band, you reduce the possibility of triggering on noise. However, this
also decreases the trigger sensitivity so that a slightly larger signal is required
to trigger the oscilloscope.
Random noise on the displayed waveform
To reduce the random noise on a signal
Pass
Band
50 kHz
Making Measurements
5-7