Oscilloscope Practical Special 9: XY Mode

Figure 1 Oscilloscope screen display in XY mode

Simply put, the XY mode converts the voltage-time display into the voltage-voltage display. In fact, in the ZDS2022 oscilloscope, the Y-axis variable of the CH1 channel input is converted into the X-axis variable in the XY mode, so the amplitude of channel 1 is plotted on the X-axis and the amplitude of channel 2 is plotted on the Y-axis, as shown in Figure 2. After turning on this mode, the oscilloscope is fixed to run with two channels.

Figure 2 Schematic diagram of the origin of Lissajous figures

In XY mode, we often use the Lissajous method for related measurements. Here is a story about the Lissajous method. About 200 years ago, a French mathematician named Lissajous invented a device that allowed a beam of light to be reflected by a mirror fixed on a tuning fork, and then reflected by a second mirror fixed on a tuning fork. The two tuning forks vibrated perpendicularly to each other, and the pitches of the two were often set to different to obtain different resonant frequencies. At the same time, the beam finally hit the wall and formed a pattern, as shown in Figure 2. This pattern is the so-called Lissajous figure. This invention is the basis of many later instruments, such as the resonance recorder.

So how do you use the Lissajous method to perform measurements in the XY horizontal time base mode of an oscilloscope? The next video will explain this in detail. Stay tuned.