Troubleshooting - UNI-T UPO2102 User Manual

User's Manual

19.2 Troubleshooting

(1) When press the button, the oscilloscope is blank screen.
a. Check whether the power is correctly connected, power supply is normal or not.
b. Check whether the power switch is really turned on. The soft power switch button should light in
green when the instrument is normal boot. And it should have relay sound.
c. If there is a relay sound, it indicates that the oscilloscope starts normally.
Try the following steps: press the DEFAULT key, then press F1, if device returns to normal, it means
backlight brightness is set too low.
d. After completing the above steps, restart the oscilloscope.
e. If the instrument still cannot work, please contact UNI-T.
(2) After signal acquisition, signal of waveform does not appear on the screen.
a. Check whether BNC port is connected properly.
b. Check whether the signal output channel has turned on.
c. Check whether the input signal channel has turned on.
d. Check whether has DC displacement in signal of information source.
e. Plug out the input signal, check whether the baseline is in the screen range (if not, please perform
auto-calibration.)
f. If the instrument still cannot work, please contact UNI-T.
(3) The measured voltage amplitude value is 10 times larger or smaller than the actual value: Check the
channel probe attenuation coefficient setting is consistent with the used probe attenuation rate.
(4) There is a waveform display but not stable
a. Check the trigger source in the trigger menu and confirm that it matches the input channel of the
actual signal.
b. Check the trigger type: general signal should use "Edge" trigger. The waveform can display stably
only the proper trigger type is used.
c. Change the trigger coupling setting to high-frequency or low-frequency reject, in order to filter out
the high-frequency or low-frequency noise that interferes with the trigger.
(5) No display after pressing Run/Stop button
a. Check whether the mode at the trigger panel (TRIGGER) is on "Normal" or "Single" and whether the
trigger level exceeds the waveform range.
b. If it exceeds，set the trigger level to the middle or set the trigger mode to Auto.
c. Press AUTO button could automatically finish the above setting.
(6) Waveform refresh is very slow
a. Check whether the acquisition method is average and the average times are large.
b. Check whether the holdoff time is large.
c. Check whether is single trigger and the current setting is slow time ase scale.
d. The above will cause slow refreshing of the waveform. It is advised to restore to the factory setting.
Waveform can be refresh normally.
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