Hi, let's check out this cool device, the Humble Oscilloscope, the most essential tool in all of electronics. What is it? Why Do you need one? And How does it work? Let's go.. But Before we take a look at the oscilloscope, both the modern digital type and the old school analog type,, we have to take a look at the multi-meter. You're familiar with the multi-meter and how it measures voltage among things..

Hence, the name multi: measures multiple things. Now We can put it on DC volts here and we can measure our battery, which is a DC source. There It is: 9.23 volts. No Worries.

Right, but what happens if this voltage changes? Hmm. Now Just imagine that you start to graph this voltage that you measure on your multi-meter. On The Y-axis Here we've got voltage and on the X-axis here, we've got time. So Let's take this one sample here, at let's say at the one second mark.

We Measure that on the multi-meter and we get our 1.5 volts or whatever it is now. What Happens if we keep actually taking a reading on our multi-meter every second or one-tenth of a second or one-fifth of a second or whatever the multi-meter updates at? You Might end up with something that looks like this. And You might have noticed it looks something like this sine wave we get in on our oscilloscope here. And That's all an oscilloscope does: is it measures voltage on the y-axis here versus time.

And If we hook our multi-meter up to our adjustable lab power supply here, we can adjust that voltage and we can see that voltage change with time. It's not just one fixed value. But If I turn this not really quick, the multi-meter really has a hard time keeping up with that. And That's a huge limitation of the multi-meter: is that it does not allow us to view these changing voltages or signals as we call them.

And Why is that a big deal? Well, because practically all modern electronics works on high-speed signals that you cannot display on a multi-meter just can't see it changing with time. So our oscilloscope is a window of voltage versus time here and we can slow it down with what's called the time base and we can display these signals now. DC is not interested. It's just a fixed line because at its at a fixed voltage.

But if we adjust that power supply whoa, look at that. It's jumping all over the place. but that's relatively slow. Good thing about the oscilloscope is it allows you to view really fast changing waveforms.

So if we use what's called the horizontal time base here, it goes from anywhere from seconds two milliseconds to $OPERAND microseconds around to nanoseconds like this and it'll just allows. The slower the time-base the slower the . moves across there. So the way we measure things on an oscilloscope is by this green here or what's called a graticule and you'll notice that it's volts per division.

1 division is one of these little squares either horizontally or vertically. That's why what's called the vertical amplify here is in volts per division. So if we're actually currently right here on one, it's one volt per division. So each time that line goes up by one division.

Bingo, That's one volt. And likewise, over here on a horizontal time-base it's in seconds per divisional. Not . Five seconds per division.

And there you go. Count it. Each time it goes across. It takes half a second to get to H division.

This case, it's not. One second. So it takes one second to sweep ten divisions across the screen there, and you'll notice that the dot goes across the screen or sweeps across the screen as it's called. and then it retraces back to the start.

That's because we don't have an infinitely long screen, but we want to be able to view waveform. so it goes across and then jumps all the way back and starts displaying again and again and again on the same screen. So if we disconnect that in feeding, no voltage at all and look where that line is, ok, it's the second division. From there, we can actually adjust that to any position that we like, and I want to explain why.

It's just handy to be able to work. do this at the moment. That's all you need to know, then. Ok, that is our reference point.

That is their ground. or zero volts. .. Now, if we plug in our signal, it's gone up 12 divisions and we're at one vote per division.

So it's one volts, 2 volts. And what do you know? We're feeding him two volts. So we're going to circuit that we're analyzing. Then we can just take our source code.

Probably chalks up we connect this onto the ground . of the circuit and then we can start probing around and having a look at some of the signals that are in our circuit. Now, we never would have been able to see these with just a multimeter. It's a window into another world.

So this signal that we just saw here. Look, it's got a ground and then it jumps up where it at. 1 volt per division here. So 123 for like four and a half volts.

So we've got ourselves a digital signal that we're looking at. We can change your time based like this. Not . 10 microseconds per division on a horizontal scale over here, so we can see the time difference between these two points.

about one, two, three, four, five divisions there or not. five microseconds between these little pulses and we can zoom in using horizontal time-base You might have noticed that this just looks like one thing, but we zoom into it. huh? Look, there's more, even higher speed signals buried within their magic. And the oscilloscope is the only tool that allows you to view this voltage versus time and to actually see all of the signals that are actually going on within your circuit is the essential tool for electronics are design troubleshooting and just understanding what's going on in your circuit.

You can't do without the oscilloscope and really, that is all you need to know. and the source code measures voltage versus time. Simple. That's it.

really. Now feeding the same signal into an analog and digital oscilloscope here. and the digital Oscilloscope works Exactly the same voltage versus time. It's got a lot more measurement functionality and things like that, but there's one crucial difference between the digital and the analog oscilloscope.

The digital one allows you to store the waveform and analyze it, so it allows you to freeze it and then work on the signal later in debug it and analyzer, but also allows you to capture single-shot events IE events that only happened once, whereas an analog oscilloscope might be able to capture that. So if you have a look at a very slow one heard signal on analog oscilloscope, you can see that you can just maybe see a trial going behind it there. That's because of the phosphor on the screen that's actually lighting up. But this is not a storage oscilloscope, so all you get is the current present value as it sweeps across.

But if you view the exact same one who'd seen on Digital Oscilloscope, look, the waveform stays there. You might be able to sit on there. it goes I'm so it stays on the screen at all times. And of course, you can press the stop button to phrase it at any time.

And if I have an event that only happens once for a brief period, we can't see it. but a digital oscilloscope. We can put it in what's called single shot mode by pressing the single button here and it'll sit here armed waiting for that event to happen. as long as you set up the trigger right.

and that's for another video until our event happens. And Bingo there's our event and we can zoom in and actually see exactly what happened there in this particular case. I Found some very interesting behavior here of when I actually switch on my signal intar function generator here using the output so it's got a relay based out with their and it's just doing something rather unusual. I didn't know that Bingo couldn't see that with an analog oscilloscope and if we hook our still scope back up to our power supply and put it in what's called a troll mode here, then and I just the past fly.

you'll be able to see I am wiggling that and you can actually see it moving in real time because it acts like a yard chart recorder. those old-fashioned are you know seismographs and things that you've seen. It's basically you can see how it's changing with time and I'm twiddling the part on my power supply and it's following that. So that's kind of like different to what we saw on the analog oscilloscope.

So that's just another way of representing now voltage versus time. but the window just slides across, it just keeps sliding going in that direction instead of that capturing. But that is the subject of another video. I'm sure.

So if I disconnect that our signals going, we can't do anything with it. But this weekend with the Digital Skype we can just press, stop, and bingo. We can go in there and we can analyze that signal even though I always stopped it and we've disconnected that from the import. We can go in there, zoom in and out, and play around with it, and analyze that signal to our hearts content.

So that is an incredibly valuable insight and the reason why you should have a digital oscilloscope over an analog one. And the modern digital oscilloscope allows us to measure all sorts of things automatically like the voltage from the peak, the negative to the positive peak here, and allows us to I get the average value, the frequency, and a whole bunch of other measurement stuff. the rise and full-time which you may not be familiar with, but all these insides into your waveform a modern digital scope can actually measure and you can turn on cursors for example. and then you can go in there and it can automatically measure the exact time for you between that cursor and that cursor of the waveform.

So you don't have to go in there and count them manually and then squint and hold your tongue at the right angle and go I Think it's near enough to that A modern digital scope can measure everything precisely. Now of course, you have a multimeter isn't completely useless. It can of course measure AC alternating current. This is where the waveform.

It goes. positive and negative voltages like that. So if we disconnected, but if we connect it up, will notice that we've got a 1 kilohertz sine wave here. and of course this can measure it, can measure the true Rms value of that changes signal and it's accurate up to a certain frequency.

Read the data sheet for your multimeter. 1.74 volts. There we go. Rms voltage.

because the digital oscilloscope can actually measure and calculate this mathematically. 1.79 volts. There's a little bit error there, but it's basically measuring the exact same thing. So yeah, this can do it.

but that's about all the motivation can do. If you want to actually see your waveform, you've gotta have an oscilloscope. And seeing is believing because this is just a number. This actually tells you what's really going on.

So there you go. I hope you learned something about Sooo Escape here. And yes, they're complicated looking things, but they so cool. They give you an insight into what's happening in your circuit.

And if you're getting into electronics you want to figure it out, you want to play around with stuff. It is the essential tool and you can buy them for a couple hundred bucks. So don't be afraid of the oscilloscope. They look complicated, but really, it's just measuring voltage versus time.

All the extra stuff is just a bonus and they're really not that hard to use when you get into it. And if you do anything, you are a beginner and you do get into trouble and things like that, you're marking around and you're doing all sorts of things and you're not sure what's going on and everything's not quite working for you and it's where's my way form. You can actually just hit the auto button and it will hopefully show you at least get your basic waveform on the screen. There it is right there and then you can start playing around with it.

although I do of course recommend that you learn how exactly how the source code works and get to know it intimately so that you can use it. Incredibly valuable tool. The Tool for Electronics Troubleshooting and I've got other our videos here which I will link in and at the end of this as well, including one where I show you how not to blow up your oscilloscope with your ground clip. lead here.

Very important. You understand ground in when it comes to a source codes and things like that, so I'll link that in down Below. Hope you enjoyed it. Catch you next time.