Measurement Of Phase And Frequency Using Cro Pdf
- and pdf
- Friday, April 30, 2021 1:30:49 PM
- 2 comment
File Name: measurement of phase and frequency using cro .zip
- CATHODE RAY OSCILLOSCOPE (CRO)
- Measure phase difference with an oscilloscope
- What is a CRO (Cathode Ray Oscilloscope) & Its Working
- Oscilloscope How To
Project Mentor: Prof.
CATHODE RAY OSCILLOSCOPE (CRO)
This tutorial will guide you through the basics of using an oscilloscope, it is meant for someone with very little or no experience with electronics or oscilloscopes. There are many types of oscilloscopes out there, and each is a little different, so I'm going to focus on the essential components that are found in all oscilloscopes and are the most useful when getting started. Oscilloscopes are useful for looking at very fast changes in voltage over time, things that we could not measure with a multimeter.
Usually when you make a measurement with an oscilloscope, you will see a line that stretches from one side of the screen to the other; this line is actually a graph of voltage vs time fig 2 , where voltage is measured along the y axis and time along the x. Oscilloscopes come in two varieties: analog and digital I'll be using a digital scope in this tutorial. The controls on both types are basically the same; be aware that the digital scopes may hide some of there controls in a menu on the LCD display instead of using knob or button.
Basically, it allows you to zoom in and out along the y axis. It allows you to zoom in and out along the x axis. Turn on your oscilloscope. If nothing is plugged into the oscilloscope you should to see a flat line, this means that the voltage of the input is not changing over time.
If you see a line that is not flat, try disconnecting the probe from the oscilloscope. If the screen is blank try the following remember all oscilloscopes are a little different, don't worry about pressing buttons if you're not sure, you won't break anything : - my oscilloscope is a dual channel scope which means it has two inputs. As shown in figure 2, pressing the "channel 1" button causes that input to display on the screen in yellow.
Pressing it again will cause it to disappear. Pressing channel 2 will display that input in blue. Your oscilloscope may only have one input no channel buttons , or it may have more than 2. Analog scopes will not display separate channels as different colors, it's all green. Once you connect to your signal, you should see the flat line turn into a waveform of some kind.
Your wave may be hard to see and appear somewhat unstable, as shown in figure 2. If it is not, turn the trigger level dial until this happens if your oscilloscope has more that one channel, make sure the trigger is set to the appropriate channel, on my scope this can be set by pushing the trigger menu button and following the directions on the lcd menu, look for the words "trigger source".
While turning the trigger level dial, you'll see a trigger level indicator move up and down the screen the small yellow triangle on the right side of the screen in the images above.
Notice that when the trigger level exceeds the height of the waveform, the signal becomes unstable. The trigger level is essentially a voltage level that your oscilloscope compares the incoming signal with, which allows it to stabilize a repeating waveshape or capture voltage spikes on the screen. Triggering can get fairly complex, there are occasions when people use external trigger sources and specify special trigger modes.
However, for most applications you will find that this is not necessary, and simply setting the trigger level to some voltage within the bounds of your incoming signal will suffice.
Before continuing on the to next step, set your trigger level to the center of the screen as shown in fig 3. The images above also provide some more detail. Also try adjusting the horizontal position so you get an idea of how that works. If you are having major problems finding your wave or centering it on the screen, ask yourself the following: -are you in AC coupling mode? The amplitude of the wave is the difference between the height of the peaks of a wave and the wave's equilibrium the value which the wave is oscillating around.
In this case I've centered the wave to oscillate around the center horizontal grid line. The distance between this equilibrium line and either the high or low peak of the wave is 2. This makes sense, since I know that in the arduino code my input in this case I set pin 8 to oscillate between 0 and 5V. This oscillation has a midpoint equilibrium of 2.
The frequency of a wave is the number of times per second that a wave repeats its shape. We cannot directly measure the frequency on the oscilloscope, but we can measure a closely related parameter called period; the period of a wave is the amount of time it takes to complete one full cycle.
As indicated in the image above, one cycle is completed in 2 horizontal grid divisions. You may have noticed the AC and DC coupling option on your oscilloscope by now. AC coupling removes the DC component of your signal so that it is oscillating around zero. For many oscilloscopes this is advantageous because it allows you to zoom in tighter on the waveform so you can measure small AC disturbances.
Your oscilloscope may also give you the option of coupling to ground. Switching to ground coupling will give you a flat line that represents the position of 0 volts. Use the vertical position control to line this up with one of the grid lines- this will be your ground marker. Switching over to AC mode will remove the DC component of your signal and show oscillations around the ground marker. In the images above I used all three coupling modes to measure a pulse-like signal oscillating between 0 and 5V.
I first put the ocilloscope in ground coupling mode to line up ground with the center line on the scope. By switching back to DC coupling fig 3 you can see my signal oscillating between V each vertical division represents 2V. If your oscilloscope has multiple channels, you can look at multiple inputs at the same time. This is especially useful for looking at changes in a signal as it moves through your circuit. Ideally, a wave going through a voltage follower should not change at all.
I measured the incoming wave on channel 1 yellow and the output on channel 2 blue. As you can see in fig 1, the waves are approximately on top of each other. Each division represents 25us, so that's a lag of about 12us. Some other examples of uses for dual channel measurements that come to mind include: measuring the response time of a sensor- compare a pulse signal to the signal out from the sensor measure phase changes analyzing at the effects of a filter.
In the introduction I mentioned that usually oscilloscope curves show the relationship between voltage and time. There are occasions where it is useful to compare the voltage of one signal verses another. This is especially useful for plotting I-V curves for diodes and other components. Figure 2 shows an x-y plot of the two channels depicted in fig 3. Channel 1 yellow in fig 3 is plotted along the x axis and channel 2 blue in fig 3 is plotted along the y axis.
Tip 1 year ago. Another very good introduction to oscilloscopes is provided by two video tutorials created by Graz University of Technology. Question 1 year ago on Introduction. Is there a way to measure delay of a single waveform. I am trying to measure the latency of an audio device by splitting the signal from the sensor and measuring the direct impulse and then the processed impulse from the device.
But the readings I'm getting are all over the place, so I must be doing something wrong. Thanks for this piece on oscilloscope. Is very informative, well detailed and straight on point.
Well done. Question 2 years ago. Can we use an oscilloscope to actually find issues? Any video I saw is always the same, explaining the function of some controls then using a signal generator to show the wave I do board level repair using a multimeter and a Amscope microscope , when having a schematic just trace the voltages, using alcohol for shorts if the board has a billion of caps.
So I bought an used scope from a retired engineer and still there, that's great to impress people when they see that but I really want to know how to use the scope, to troubleshoot a circuit which I don't have schematics. Where should I look? Whats the output patterns?
Question 2 years ago on Step 6. Its like the data was interrupted or something! Question 2 years ago on Step 7. Question 3 years ago on Step 2. In 1 mega hz oscilloscope, If i give 1 Volt and 1 mega hz , why the output is doubling , i mean its showing 1.
When I input two channels on the oscilloscope one of them is unstable , how to adjust the trigger to stabalize both channels inputs????? Reply 4 years ago. Of course you have figured that out by now. For newcomers; this is happening because the trigger is correctly applied to one channel not the other.
To apply trigger on the other channel, select the trigger menu this is usually a dedicated button near the trigger control knob of your scope. Now you will see a new menu pop up. In the menu there is an option to select "source" you can change the channel to trigger here. Change it to select the unstable channel and now adjust the trigger. Reply 5 years ago on Introduction. The output from an Arduino pin is DC. Pure DC wouldn't be all that helpful, so you start toggling the output every now and then and this gives you pulsating DC.
When not specified otherwise, most hobbyists automatically think voltage , when thinking about AC vs DC, but if you realize, that it means Alternating Current and Direct Current , perhaps it gets easier to grasp.
Alternating Current means, that the current changes direction, at the frequency in question, while a pulsating Direct Current only goes in one direction, although in pulses, like if you do Morse code with an old incandescent flashlight, the current goes into the bulb and stops going into the bulb - pulsating DC however slow. Connecting the same bulb to AC via e. An example of where you would remove the DC could be, when you have a low amplitude AC superimposed on a much higher DC voltage, say you have a 10mV AC signal riding on a 12V supply whether it be some noise or a legit signal and you want to inspect the AC - while you could offset some 'scopes for 12V, the DC could be higher than the 'scope is able to offset there's other reasons too, but lets keep to that , so, you "AC couple" the input by a capacitor and blocks static DC.
If the DC was pulsating as well, you wouldn't be able to suppress it and it would be hard to inspect the AC, as with a 12V signal on an 8-bit 'scope, each bit represent more than 46mV techniques to enhance the resolution do exists, but is way outside the scope of this example. Now if your smallest quantum is 46mV, the 10mV that you want to inspect is about a quarter of the LSB and as such has vanished as far as the 'scope is able to show.
Introduction: Oscilloscope How To. By amandaghassaei uh-man-duh-guss-eye-dot-com Follow.
Measure phase difference with an oscilloscope
Project Mentor: Prof. CRO is a basic instrument employed for the study of several types of waveforms. It can measure various quantities such as peak voltage, frequency, phase difference, pulse-width, delay time, rise time, and fall time. It comprises of a cathode-ray tube CRT , and input circuitry for focusing and amplification. In this graduated the topic of his research is the oscillations of elastic strings.
cathode ray oscilloscope and to make use of Lissajous figures for phase and frequency measurements. Theory. • Measurement of Voltage Using CRO. A voltage.
What is a CRO (Cathode Ray Oscilloscope) & Its Working
This tutorial will guide you through the basics of using an oscilloscope, it is meant for someone with very little or no experience with electronics or oscilloscopes. There are many types of oscilloscopes out there, and each is a little different, so I'm going to focus on the essential components that are found in all oscilloscopes and are the most useful when getting started. Oscilloscopes are useful for looking at very fast changes in voltage over time, things that we could not measure with a multimeter. Usually when you make a measurement with an oscilloscope, you will see a line that stretches from one side of the screen to the other; this line is actually a graph of voltage vs time fig 2 , where voltage is measured along the y axis and time along the x.
CRO is a very versatile instrument in laboratory for measurement of voltage, current, frequency and phase angle of any electrical quantity.
Oscilloscope How To
Phase difference can be measured on an oscilloscope by determining the time delay between two waveforms along with their period. All periodic signals can be described in terms of amplitude and phase. We all learned that in basic circuit theory. Fortunately, you can also measure phase with an oscilloscope using several methods. The phase of a periodic electrical waveform describes a specific position at a point in time.
The CRO stands for a cathode ray oscilloscope. It is typically divided into four sections which are display, vertical controllers, horizontal controllers, and Triggers. Most of the oscilloscopes are used the probes and they are used for the input of any instrument.
Cathode Ray Oscilloscope. 2. Measurement of Phase and Frequency using CRO. 3. Measurement of Frequency and Power Factor.
Leave a comment
Essentially a cathode negative electrode is heated and electrons boil off the surface to be attracted by a series of anodes positive electrodes. The deflection system consists of two pairs of parallel plates called X-plates and Y-plates. To display a waveform, a repetitive reversing voltage is applied to the X-plates. This causes the electron beam to be slowly repelled from the left-hand plate and attracted towards the right-hand plate. On the CRO screen this translates as an illuminated dot moving from left to right. The voltage is then reversed and increased rapidly.
Facebook Twitter. It is a very important oscilloscope used to analyse the waveform and measure them. Now here we will discuss how the measurement of waveform i. It is interesting to consider the characteristics of patterns that appear on the screen of a CRT when sinusoidal voltages are simultaneously applied to horizontal and vertical plates. These patterns are called 'Lissajous Patterns'.
Привет, это Дэвид. - Он замолчал, не зная, что сказать. Беккер терпеть не мог говорить с автоответчиком: только задумаешься, а тот уже отключился.