Intro to electronics

A not so ordinary morning

It's Tuesday, your cell phone alarm goes off at 6:30 a.m. You're so tired that you don't even have the energy to complain. You fumble for the snooze button, miss it... and it's too late: your brain has switched on. Suddenly you ask yourself: How does the alarm on my phone actually work? And, for that matter, how does the cell phone itself work?

Then a strange feeling comes over you: you realize that you have no idea how your phone works, or most of the electronic gadgets you see all the time. You can look for a simple explanation and go back to sleep:

• "It doesn't matter, it works and that's it."
• "It must have been designed by some geeks somewhere."

With that you relax, close your eyes and squeeze five more minutes of sleep. Or not.

If, instead of sleeping a little longer, your mind keeps mulling over the subject, you'll want to keep reading this text.

What is electronics and why should you care?

We live surrounded by electronic devices. They are so ubiquitous that we don't even stop to think about them. But even the simplest devices are enormously complex. Imagine a light bulb. It seems like the most basic thing, right? And yet, questions immediately arise:

• What's inside the glass and how does it work?
• Why does it make light?
• What are the "W" (Watts) on the box?
• Can I replace it with one with fewer W? With one with more?
• Why do some of them blink when recording them with your mobile phone (try with slow motion function)?

You may have an intuition for all the answers, although some of them hide a much deeper answer than it seems at first glance. Electronics is related to all of them, although it does not provide a complete answer to some of them. But hey, you don't have to stress either, you don't need to know everything in life.

If we transfer the exercise done with the light bulb to something more complex (a TV, a cell phone, an electric piano, an electric car motor, or a computer), then the questions and answers could take more than an entire professional lifetime to answer. Just to give a few examples

• Why does the character jump when I hit the X of the PlayStation controller?
• How are TV images formed?
• How is it possible to read this text, if it was written at another time and in another place?
• Why does sound appear from an amplifier when playing the strings of an electric guitar?
• Why can I listen to music streaming from my car?
• How does an electric car move?

In the end, it all comes down to this: electrons move, and we've learned to control them to do useful things (it's a bit more complex). Put like this, it seems simple, but achieving it requires many areas of knowledge that fit together like the pieces of a puzzle. It is very rare for a person to have solid knowledge in all areas, although delving into one of them, and having a reasonably good view of the others, is usually possible. I see the relationship between them as if they were layers of knowledge that support each other. A certain level of the structure assumes that everything below is solid and is concerned only with how to build its floor. Something like this:

In the figure, on the right are the fields of knowledge or "floors" that make everyday electrical gadgets work. On the left, the studies or professional careers that address them. The green color means an elevated dominance of the "floor" of the structure. Red is superficial knowledge. The "floors" shown are a tremendous simplification of reality. In reality, there are mezzanines, balconies, adjacent buildings...

When you are working on a product or trying to solve a problem, you typically focus on the “floor” you are working on and assume that everything below it is under control. For example, an electronics engineer works with components that they combine in a certain way to achieve a goal, but they don't consider how those components are made. Similarly, software developers assume that all the parts of the PC/server have been designed and are functioning properly. It is true that sometimes it is necessary to investigate what is happening on the "floor" below.

To get a better idea, think about the alarm clock phone we talked about. At the lowest level is physics, which explains how electrons behave within semiconductor materials. Above that is electronics, which organizes those semiconductors into circuits and chips capable of performing calculations, storing data, or generating signals. On a higher level is firmware, which is like a layer of very basic instructions that tells the hardware how to start up and function. Higher up is telecommunications, which allows your cell phone to connect to WiFi or 5G networks and send information anywhere in the world. And on the top floor is software, the apps you use every day: WhatsApp, your browser, the alarm that went off in the morning. Each layer depends on the one below it, like in a well-built building: if one fails, everything above it shakes.

In my opinion, the easiest way to achieve a sense of "complete" understanding is through knowledge of electronics and communications, that is, the intermediate "floors".  The physics part is very interesting, but it is so complex that it goes very detailed, very fundamental, so it is difficult to relate it to the complete operation of a gadget. The computer or software part is also interesting, but the field has developed so much that one can do SW practically without having to know anything about what is on the lower "floors". So now we have an idea of what knowledge we need to acquire in order to have a reasonable understanding of how things that seem magical in our times work.

And how do you learn electronics without studying for a degree?

Okay, that sounds good, but you may be wondering: where do I start? The short answer would be: with books and years of study. But that's not the only option. If you're looking to enjoy yourself, understand the basics, and carry out your own projects, there are more practical ways.

Think about how you've learned other things in your life: by reading manuals or by doing them? Probably the latter. The same is true for electronics. And the good news is that you don't need a lab full of equipment: today there are very powerful circuit simulators that allow you to experiment without spending a penny.

Your turn

If you've made it this far, we'd love to hear from you.

• What attracts you to electronics?
• What projects do you have in mind?
• If you already know something, what got you hooked and what can you share with others?

This space is designed to learn together, so welcome to the trip!