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Digital Oscilloscope

The following demonstration is very dangerous because of LIVE electricity !!!

Digital Oscilloscope ƽXܪi
RMB $500

Pay attention to the values of div, Vrms and the wave form
div = 50.0ms, 230.6Vrms

div = 10.0ms, 230.7Vrms

div = 2.00ms, 217.0Vrms

Multimeter mode
For the Multimeter mode, the TrueRMS value is 225.6V

This time, pay attention to the scale of the oscilloscope and the wave form

scale is 100V

moved the wave form downward to show the peak

This graph shows the peak is flat


A.C. should be Sine Wave, but the result is different ... ... this may be due to

  • The accuracy or precision of the Digital Oscilloscope is not good for this price range.
  • The A.C. supply in Hong Kong is not perfect.
  • Interference occurs in the power network
Using another Multimeter, the Vrms is 226.9V
This is my first time owning and using a Digital Oscilloscope, I have many to learn; however, Oscilloscope is a very useful tool to check the signals. RMB $500 is a good price for a poor DIYer.