Rigol DS2000E Series User Manual page 270

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(4) Change the trigger coupling type: if edge trigger is currently selected, press
MENU (in the trigger control area (TRIGGER) on the front panel) 
Setting  Coupling to select "HF Reject" or "LF Reject" to filter out the
high-frequency or low-frequency noise that disturbs the trigger.
(5) Change the trigger holdoff setting.
5. No display after pressing RUN/STOP:
Check whether the trigger mode in the trigger control area (TRIGGER) on the
front panel is "Normal" or "Single" and whether the trigger level exceeds the
waveform range. If yes, set the trigger level to the middle or set MODE to
"Auto".
Note: Using AUTO could automatically finish the above setting.
6. The display of waveform is ladder-like:
(1) The horizontal time base might be too low. Increase the horizontal time
base properly to improve the display.
(2) If the display type is "Vectors", the lines between the sample points may
cause ladder-like display. Press Display  Type to set the display type to
"Dots" to solve the problem.
7. Fail to connect a PC or a PictBridge printer through USB:
(1) Press Utility  IO Setting  USB Device to check whether the current
setting matches the device currently connected.
(2) Check whether the USB cable is correctly connected to the oscilloscope.
(3) Check whether the USB cable is in good condition. If needed, restart the
oscilloscope.
8. The USB storage device cannot be recognized:
(1) Check whether the USB storage device can work normally.
(2) Make sure that the USB storage device being used is flash storage type.
This oscilloscope does not support hardware storage type.
(3) Make sure whether the capacity of the USB storage device is too large. It is
recommended that the capacity of the USB storage device being used with
this oscilloscope is no larger than 8 GBytes.
(4) Restart the instrument and then insert the USB storage device to check it.
(5) If the USB storage device still cannot be used normally, please contact
RIGOL.
15-2
Chapter 15 Troubleshooting
DS2000E User's Guide