DPO6000, MPO6000 Series Digital Fluorescent Oscilloscope Product Manual V1.3 Phase difference measurement schematic 𝐴 𝐶 According to sin 𝜃= 𝐵 or sin 𝜃= 𝐷 , θ is the phase difference angle between the chan- nels, and the definitions of A, B, C, and D are shown in the figure above. Therefore, the phase difference angle can be obtained, that is: θ = ± arcsin 𝐵 Or θ = ± arcsin 𝐴 𝐷 𝐶 If the major axis of the ellipse is in the quadrants I and III, then the obtained phase dif- ference angle should be in the quadrant III, that is, within (0 to π / 2) or (3π / 2 to 2π).
If the major axis of the ellipse is in the quadrants II and IV, then the obtained phase dif- ference angle should be in the quadrants II and III, that is, within (π / 2 to π) or (π to 3π / 2). The X-Y function can be used to test the phase change of a signal through a circuit network. Connect the oscilloscope to the circuit and monitor the input and output sig- nals of the circuit. Note: When XY mode is turned on, Scan Mode is automatically turned off. In XY mode, the oscilloscope automatically selects the channel combination "CH1- CH2" or "CH3-CH4". In XY mode:
"Scan mode", "Vector display", "Protocol decoding", "Acquisition mode", "Pass / Fail test", "Digital channel", "Persistence time" have no effect. XY single window display mode 30 The signal must be centered horizontally ⅡⅠ B A D C Ⅲ Ⅳ Ⅱ D C Ⅰ A B A Ⅲ Ⅲ Ⅳ B D