Rigol DS6000 Series User Manual page 286

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signal should use "Video" trigger. Only when the proper trigger type is used,
can the waveform be displayed stably.
(3) Check the trigger level: adjust the trigger level to the middle position of the
signal.
(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 the trigger control panel (TRIGGER) on the front panel to check whether
the trigger mode is set to "Normal" or "Single" and whether the trigger level
exceeds the waveform range. If yes, set the trigger level to the middle or set the
trigger mode to "Auto".
Note: Using the Auto key 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 DISP  Type is set to "Vectors", the lines between the sample points
may cause ladder-like display of the waveform. Set Type to "Dots" to solve
the problem.
7. Fail to connect the PC or PictBridge printer through the USB interface:
Press UTIL  IO Setting and check whether the setting in USB Device
matches the currently connected device. 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 4 GBytes.
(4) Restart the instrument and then insert the USB storage to check it.
(5) If the USB storage device still cannot be used normally, please contact
RIGOL.
15-2
15 Troubleshooting
DS6000 User's Guide