The first time I laid eyes upon an oscilloscope, I had just started working as a research assistant for a physics lab on my university campus. My first thought was “what’s this clunky, beige rectangle thing?” .
That thought quickly evolved into “why is this clunky beige thing so expensive?!”
But then I soon discovered that these devices are incredible and insanely powerful pieces of technology. Oscilloscopes have helped us understand so much about the world around us. They help us analyze circuits, learn more about stars, and probe the depths of the ocean.
They do this by measuring electrical signals in voltage over time. Waveforms are collected and can be analyzed for frequency, amplitude, period, etc. There are three main types of scopes – analog, digital, and PC based. I have summarized and outlined the uses of each type below.
Analog: These oscilloscopes, which are also sometimes known as oscilloscope CRTs, are essentially what you’d find in an old TV – cathode ray tubes. These scopes only display a single event as it occurs, and can only be stored if you have a second piece of equipment called an image storage tube, which is essentially an electron gun (or electron emitter).
Digital: These oscilloscopes save data digitally. Saving data digitally is advantageous due to the fact that the data will stay saved for an indefinite amount of time and the images are more crisp. You can plug in a USB drive and transfer saved data onto a computer for analysis, adjust the brightness of the scope, and the digital memory works a lot faster than analog memory does. On the scope itself, it can instantaneously tell you information about your waveform, such as amplitude, frequencies, and more.
PC Based:These scopes are way smaller and less bulky then their counterparts. They can simply be plugged in to a computer via USB; using their support software, your PC basically becomes the oscilloscope screen.
A great example of a PC based oscilloscope is the Analog Discovery 2 (pictured above) and the accompanying WaveForms 2015 software. If you are not familiar with the software, WaveForms is free, powerful, and you can use it with (or without!) the Analog Discovery itself. It also acts as a function generator and can generate different waveforms (sine, cos, square, etc.). PC-based scopes are ideal for educational purposes. They’re relatively cheap, small, and are great for classrooms or home offices. In the research lab I worked at we mainly had digital scopes. Looking back, I wish I had picked up an Analog Discovery 2 earlier!