A digital oscilloscope is a device or piece of equipment used to check out all kinds of signals in a variety of ways. For electronic technicians and electronic engineers, you will use digital oscilloscopes to watch how signals change in circuits you can also use this equipment to locate any fault in radios, television and other similar pieces of equipment.
Like a tester or digital multitester, an oscilloscope has probes to let you feed in electric currents through coaxial cables. You can also attach a transducer and use the device to measure just about anything. A microphone can be used together with an oscilloscope to study sound waves. You can attach a thermocouple to study temperature changes in a system. You can also use a piezoelectric transducer to study vibrations.
How a Digital Oscilloscope Works
A digital oscilloscope works like a cathode-ray tube television. In a TV, electron beams are made to scan back and forth a screen coated on the back with chemicals called phosphors. Every time the beam hits the screen, these light up the phosphors. The electron beams sweep across the entire screen and build up the picture that is seen on the screen. Electron beams do it all over again until you see a moving picture. In an oscilloscope, electron beams work the same way creating a picture graph. When you see a line drawn on the screen of the oscilloscope this is actually an electron beam moving up and down.
The electrical signals drawing into the x and y connections become the x and y values on your on-screen chart. Because there is a one-to-one relationship between these two, a traditional oscilloscope is an analog device.
How do You Use a Digital Oscilloscope?
1. Connect the signal you want to study to the y-circuit and use the x-circuit to find out how the signal varies over time.
2. You can connect the second signal to the x-circuit and then study how the y and x signals behave and vary together.
3. Switch the oscilloscope on and plug it into a signal. You will see a trace forming against the background of the on-screen graph.
4. If the trace is too small to adjust the calibration of the x and y-axes. This is just like using a differently sized scale when you’re plotting a chart on paper.
5. Turn the Time/Division control or Time/Div or Secs/Div. This will alter each x-axis division of the screen so the incoming signal can take more time to move across.
6. Turn on the Time/Division control to set to 0.5 seconds per division. This will spread out to take up the twice as much horizontal room. This is now represented by two divisions on the screen.
7. Adjust the y-axis control labeled Volts/Division or Volts/Div the same way. Make the trace larger to fill the entire screen so you can use the graticule for more accurate measurements.
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Types of Digital Oscilloscopes
There are a variety of oscilloscopes. The first ever or traditional oscilloscopes were based on cathode-ray tubes (CRTs). These are large and heavy; require large amounts of power and expensive. Basic oscilloscopes are also unreliable and therefore these were replaced by more convenient and reliable LCD oscilloscopes.
1. LCD Oscilloscopes
Instead of using moving electron beams to draw graphs and traces, LCD oscilloscopes use digital electronics. These are more effective because these can mimic what’s happening with older technology. LCD oscilloscopes are very easy to carry anywhere because these are made of light materials. These are less expensive and compact. Some LCD oscilloscopes can even fit your pocket.
Compared to using traditional oscilloscopes that use analog technology (these devices display different signals on the screen that correspond according to the signals you feed into them), LCD oscilloscopes are digital. These use analog-to-digital converters to turn incoming analog signals into numeric or digital form. The values are then plotted on the screen.
2. USB Oscilloscopes
Because your computer, tablet, or smartphone already has a CRT or LCD display, you don’t need to buy an oscilloscope if you are just going to use one for occasional hobby use. Cleverscope is a company that sells inexpensive, plug-in oscilloscopes that simulate the circuitry in a traditional oscilloscope. This kind of oscilloscope uses USB connectors or corresponding leads that will work with mobile devices. This will display a trace on your PC or mobile screen. A USB oscilloscope can be used on the go or in the field however some technicians and engineers still prefer to use reliable LCD oscilloscopes.
How to Use an Oscilloscope