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Hello everyone, today we will learn about the main parameters of the oscilloscope

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The main parameters of the oscilloscope include the bandwidth of the oscilloscope,

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the refresh rate, and the sample rate

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Here are the three key parameters we need to focus on

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When we buy an oscilloscope, we must choose the oscilloscope that suits us

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One of the things we're more concerned about is the bandwidth

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Bandwidth refers to the maximum frequency that the oscilloscope can measure,

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but there is also a certain degree of error

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For example, there are 50M bandwidth, 100M bandwidth, 200M bandwidth, etc.

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We are engaged in computer maintenance,

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and an oscilloscope with a bandwidth of 100M to 200M is basically enough

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The second is the refresh rate,

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which is also a very important parameter

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What does refresh rate mean?

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The higher the refresh rate, the less dead time it has, the waveform is not easy to be distorted,

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and the original waveform can be restored to the greatest extent

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An oscilloscope with a high refresh rate has more sampling times

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An oscilloscope with a low refresh rate has less sampling times and has a large dead time

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Another important parameter is the sample rate

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For example, when it is collecting this section of waveform,

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is the collected waveform original?

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It depends on whether it has enough sampling points, that is, whether the sample rate is high enough

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What is sample rate?

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For example, the red one is the original waveform,

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and the blue one is the sampling point

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Collect this place once, collect here, and collect again here

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Connecting the waveforms collected by these sampling points is the green waveform,

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which is the waveform displayed on the screen

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In this case, it is still a little different from the original waveform,

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because its sampling points are not enough

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If the sampling points are very dense,

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the waveform can be restored to the greatest extent

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You can see that there are still missing parts here,

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because there are not enough sampling points, that is, the sample rate is not high enough

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If the sample rate is high, this part can be captured

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This is called the sample rate

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From signal input to waveform display, if the processing speed is not fast enough,

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a large number of dead zones and delays will be generated

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What is displayed on the screen is a digital signal,

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which is converted into a digital display signal by the microprocessor and displayed on the screen

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The waveform collected by the probe is an analog signal

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Therefore, there will be analog and digital conversion in the middle

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It is necessary to convert the collected analog signal into a digital signal,

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process it, and then display it

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These are the main parameters of the oscilloscope