User`s guide

RIGOL

User’s Guide for DS1000E, DS1000D Series

3-4

Example 4: To Reduce the Random Noise on a Signal

If the signal is noisy (Figure 3- 2), set up the oscilloscope to reduce the noise on the

waveform and avoid its interference to the signal.

Figure 3- 2

Waveform display

1. Set the probe and the channel attenuations to 10X.

2. Connect a signal to the oscilloscope and obtain a stable display.

3. Improve the trigger by setting the Coupling.

(1) Press the MENU in the Trigger control area.

(2) Press Set Up→Coupling→LF Reject or HF Reject

HF Reject (High frequency reject) adds a low pass filter with the -3 dB cut-off point

at 150 kHz. Use HF rejects to remove high frequency noise such as AM or FM

broadcast stations from the trigger path.

LF Reject (Low frequency reject) adds a high pass filter with the -3 dB cut-off point

at 8 kHz. Use LF Reject to remove low frequency signals such as power line noise

from the trigger path.

4. To reduce the noise by setting the acquisition type and adjust the waveform

intensity.