How Does an Oscilloscope Work? – The Ultimate Guide!

Avatar of Murray Slovick
Murray Slovick
Administrator at - OscilloscopeTools

Being an Electrical engineer, Murray never limits himself with the job he’s doing. He constantly explores new branches of technology that are relevant to his...Read more

An oscilloscope is a device that allows you to see the electrical signals that are happening in your circuit. It does this by taking the signal and turning it into a visual representation on the screen. This can be really helpful for troubleshooting issues with your circuit or just understanding how it works. So, here I am about to explain how does an oscilloscope work.

How does an oscilloscope work? Well, it takes the signal through the input then that signal reflects on a CRT screen. And the CRT has a deflection plate that deflects the signal according to intensity. Therefore, you will get a waveform of the signal to measure it properly.

Keynote

  • An oscilloscope is one of the essential tools for measuring electrical signals.
  • It has a screen that can be CRT or LCD
  • There are two types of oscilloscopes such as digital and analog.
  • And, it can measure current, voltage, frequency, phase difference.

Overview of an Oscilloscopes

An oscilloscope is an electronic test instrument that allows the user to view the waveform of an electrical signal. Oscilloscopes are used in various applications, including troubleshooting, design, and production.

Overview of an Oscilloscopes

Oscilloscopes work by using a CRT (cathode ray tube) to display a graph of the voltage of an electrical signal over time. The signal’s voltage is displayed on the y-axis of the graph, and the time is displayed on the x-axis. The oscilloscope can be set to display the signal in a variety of ways, including as a waveform, as a spectrum, or as a waterfall.

Types of Oscilloscopes

According to the basic fundamentals and uses, there are three primary types of oscilloscopes: analog, digital and mixed-signal.

Analog oscilloscopes

Use a CRT (cathode ray tube) to display the waveform of an electrical signal. The waveform is displayed as a series of horizontal lines on the screen. The voltage and time period of the signal is measured by the position of the lines on the screen.

Analog oscilloscopes

Digital oscilloscopes

Use a digital storage oscilloscope to store the waveform of an electrical signal. The waveform is displayed on a computer screen as a series of dots. The voltage and time period of the signal is measured by the position of the dots on the screen.

Digital oscilloscopes

Mixed-signal oscilloscopes

Use a combination of an oscilloscope and a logic analyzer to measure signals with better efficiency. Therefore, it will get an oscilloscope’s accuracy and the versatility of a logic analyzer. Also, it can connect with a computer to make work easier.

Mixed-signal oscilloscopes

Important Parts of an Oscilloscope

An oscilloscope is a combination of various small parts. But, there are four parts that are the most important among all. These are CRT, Vertical control, Horizontal control, and Triggering control.

But, let’s see the circuit diagram of the oscilloscope first.

CRT screen

In an oscilloscope, the cathode ray tube is used to display a graph of the voltage or current at a given point in time. The voltage is applied to the cathode, and the ammeter measures the current. The electrons are then accelerated towards the anode, and the voltage controls the beam’s intensity. This creates a beam of electrons that scans the screen from left to right, and the beam’s intensity is proportional to the current.

Vertical control

A vertical control in an oscilloscope adjusts the voltage displayed on the screen. The height of the waveforms determines this voltage on the screen. The higher the waveforms, the higher the voltage. The vertical control allows you to adjust the voltage to match the waveforms on the screen.

Horizontal control

Horizontal control allows the oscilloscope to display a single horizontal line on the screen. It can be used to adjust the timebase, which is the time it takes for the oscilloscope to draw a single horizontal line on the screen. This is measured in milliseconds (ms) and can be adjusted by turning the horizontal control knob. The horizontal control can also be used to adjust the sweep speed, which is the speed at which the oscilloscope scans the screen. This is measured in seconds per division (s/div) and can be adjusted by turning the horizontal control knob.

Triggering control

Triggering in an oscilloscope controls the timing of the waveform display. The waveforms are displayed in the time domain, so triggering is used to control the start and stop times of the waveforms. Triggering is also used to control the acquisition of data.

There are two types of triggering: edge triggering and level triggering. Edge triggering is used to detect when a waveform has crossed a certain voltage level. Level triggering is used to detect when a waveform has reached a certain amplitude.

Triggering is controlled by the trigger level and the trigger slope. The trigger level is the voltage level or amplitude the oscilloscope will start acquiring data. The trigger slope is the voltage change that must occur to trigger the oscilloscope.

The oscilloscope will trigger on the rising edge or the falling edge of the waveform. The rising edge is when the waveform reaches the trigger level and starts to increase in voltage. The falling edge is when the waveform reaches the trigger level and starts to decrease in voltage.

How Does an Oscilloscope Work?

In its simplest form, an oscilloscope is a device that takes an electrical signal and graphs it over time. The image is called a waveform. By looking at the waveform, you can see how the signal changes over time. This can help troubleshoot electrical problems or for understanding how a circuit works.

How Does an Oscilloscope Work

How Analog Oscilloscopes Work

Analog oscilloscopes work by taking a voltage input and displaying it on a screen. The input is connected to the oscilloscope’s vertical input, and the screen is divided into horizontal lines that represent time. The time at the left of the screen is at the top, and the time at the right of the screen is at the bottom.

How Analog oscilloscopes work

The oscilloscope then draws a graph of the voltage input over time. The voltage input is shown as a line on the graph, and the time is shown as a horizontal line. The oscilloscope can also show the voltage input as a waveform, which accurately represents the voltage input.

Analog oscilloscopes are used to measure the voltage input and to see how it changes over time. They can also be used to diagnose problems with electrical equipment.

How Digital Oscilloscopes Work

Digital oscilloscopes work by sampling voltage at a fixed rate and displaying the voltage waveforms on a digital screen. The voltage waveforms are displayed as a series of dots representing the voltage amplitude at a specific point in time. The oscilloscope samples the voltage waveforms at a fixed rate and calculates the average voltage between the samples. This process is repeated for every sample, and the resulting waveform is displayed on the oscilloscope’s screen.

How digital oscilloscopes work

What Can We Use Oscilloscopes for?

It is obvious that an oscilloscope is used to measure electronic signals. By doing that, you can troubleshoot an electronics circuit. And it has a wide variety of uses in engineering fields. But the following are the most common uses of an oscilloscope.

What Can We Use Oscilloscopes for

Voltage Measurement

When measuring voltage, an oscilloscope is often used to display the waveforms of electrical signals. Voltage is the electrical potential difference between two points in a circuit. The oscilloscope can be used to measure the voltage of an AC or DC signal by connecting the oscilloscope probes to the points in the circuit where the voltage is to be measured.

Current Measurement

Current measurement is related to the voltage measurement. Measuring current using an oscilloscope is pretty simple. First, attach a resistor between the circuit then measure its voltage. After that, remove the resistor and measure the voltage again. Now, if you divide those readings, you will get the current.

Frequency Measurement

An oscilloscope is a device that is used to measure the frequency of a signal. The oscilloscope works by displaying a graph of the signal on a screen. The signal’s frequency can be determined by measuring the time it takes for the signal to go from one edge of the screen to the other.

Phase Difference Measurement

Phase difference measurement is the process of using an oscilloscope to measure the phase difference between two signals. This process is used to determine the time delay between two signals and can be used to calculate the distance between two points.

To measure the phase difference between two signals, you first need to connect the signals to the oscilloscope. The oscilloscope will then display the signals as two waveforms on the screen. It can determine the phase difference of the two signals by measuring the time difference between the two waveforms.

It can also be calculated by measuring the distance between the two waveforms. You can do this by measuring the amplitude of the waveforms and then converting the measurements to distance.

Conclusion

Suppose you ask me how an oscilloscope works and tell me to give a short answer. It takes the signal input then measures that show the readings. Therefore, you can troubleshoot an electrical circuit. Since it can measure voltage, current, frequency, and phase difference, you will know where the problems lie in the circuit. And that will help to accelerate your troubleshooting and fix the circuit quickly.

Being an Electrical engineer, Murray never limits himself with the job he’s doing. He constantly explores new branches of technology that are relevant to his field. Besides his profession, he’s a hobbyist blogger, and researcher. He creates this site “Oscilloscopetools” because he wants to share his expertise about oscilloscope tools with a broader audience who don’t have much knowledge about these tools.

Leave a Comment