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Some people might get confused by the plethora of theoretical knowledge related to oscilloscopes when using one for the first time, which can lead to a loss of interest in learning about it. If we could first learn *how to measure a simple signal*, gaining a quick start and a sense of achievement, it might give us more motivation to learn *and understand oscilloscopes*. Based on this idea, before learning some theoretical knowledge, we can first take a look at how to use an oscilloscope to measure a simple signal. Prepare the tools: an oscilloscope and probes. Step 1: Turn on the oscilloscope, then connect the probes to it. https://pic1.zhimg.com/80/v2-9c255e6601b270d85b22d28cb1a867f4_720w.jpg Step 2: Locate the square wave calibration signal output terminal on the oscilloscope. https://pic4.zhimg.com/80/v2-f0360303c7206fb0dffe2c52537bba27_720w.jpg Step 3: Hook the probe’s tip onto the calibration signal output terminal, and use the probe’s ground clip to connect it to the ground terminal. https://pic1.zhimg.com/80/v2-92e0d25fe777999cfdaff8f15b3674a4_720w.jpg After making these connections, the oscilloscope may display various patterns like this: https://pic3.zhimg.com/80/v2-d1d8f345f3b37d990a14bded37d6cbde_720w.jpg Hm, why does it look different from what I imagined? Shouldn’t the square wave look like this? https://pic2.zhimg.com/80/v2-902b227967fd74f346e36d18080d4ad9_720w.jpg Don’t worry; Step 4: Press the “auto” button on the oscilloscope. https://pic4.zhimg.com/80/v2-5a02edb0a365837ce306e42b0d9982d7_720w.jpg That’s it – we’ve now successfully measured a signal: https://pic4.zhimg.com/80/v2-c04c8ec89a08cda33142567bb36771e7_720w.jpg Of course, you might think it’s too simple – just use the auto function and it’s done I want to generate the waveform myself. So next, we’ll talk about how to adjust it by yourself. Abnormal waveform display is usually due to two reasons: the first reason is that the waveform is displayed too large and goes beyond the screen boundaries, or too small and becomes compressed together making it impossible to see clearly. https://pic2.zhimg.com/80/v2-4b9523d7016d431908c1c72a70ce9ca1_720w.jpg It’s too large in the horizontal direction; it’s too small in the horizontal direction. https://pic2.zhimg.com/80/v2-5b46288d27d29872415cdd21c2ca3725_720w.jpg It’s too large in the vertical direction; it’s too small in the vertical direction. Let’s take a look at how to adjust this: since it’s too large in the horizontal direction, we need to make it smaller ； If it’s too crowded in the horizontal direction, we need to expand it. As shown in the figure below, operation via the touchscreen or by turning the knob is sufficient; this button is referred to in technical terms as the time base, and it controls the time duration of one grid on the horizontal axis. https://pic2.zhimg.com/80/v2-765e8bfe42a453b045393efdab52920d_720w.jpghttps://pic1.zhimg.com/80/v2-689672ddc266f3267a36b1b98f840bb8_720w.jpghttps://pic1.zhimg.com/80/v2-58d0f78d69692e7c9b366c82bd284ba8_720w.jpg It’s too large in the vertical direction; we need to reduce it ； It’s too crowded in the vertical direction, so we need to expand it. As shown in the figure below, operation via the touchscreen or by turning the knob is sufficient; this button is professionally referred to as the vertical gear, and it controls the voltage value for one unit on the vertical axis. https://pic1.zhimg.com/80/v2-6699035ca6489174d2e59ded33a63a18_720w.jpg After adjusting the time base and vertical settings, you might encounter another issue: the waveform keeps shaking back and forth, showing instability, just like this: https://pic4.zhimg.com/80/v2-d1b7b734b04bec1c223736f3975e7fcb_720w.jpg This is the second reason for abnormal waveform display: the trigger level has not been adjusted to the proper value. First, we click on “Level” located on the right side of the waveform display area: https://pic4.zhimg.com/80/v2-5fc653a2e3ccc4a1d9da8b7c106cf733_720w.jpg Then, we hold our finger over the black-colored area and slide it upwards: https://pic3.zhimg.com/80/v2-b25ac45ed7fdd70ca67cd0839bf2eeaa_720w.jpg Once the trigger level moves inside the waveform, the waveform becomes relatively stable. https://pic4.zhimg.com/80/v2-64382d6ec1e28d04e88e7deee95e13eb_720w.jpg Or turning the Level knob in the Trigger area can achieve the same effect: https://pic2.zhimg.com/80/v2-80827e9b1cca22ea27a26b9be613e90d_720w.jpg Of course, for the waveform to be stable, it is necessary that the signal itself is periodic. Try it out yourself, as this will help you understand the entire process better. No matter what type of waveform you are measuring, you can adjust it to the appropriate position by following this approach.