My interest in electronics goes back many years. When I was in seventh grade, my father helped me build a crystal radio. I still remember the fascination of hearing a radio station through a device that required no batteries at all. Not long afterward, we assembled a Heathkit stereo together, which at the time felt like building a truly sophisticated piece of equipment. A little later I built a Heathkit fuzz box for my brother’s guitar, and at one point I even managed to bring an old shortwave radio back to life after it had stopped working. Over the years I continued to tinker with small projects like these whenever the opportunity arose.
Looking back, I sometimes think I should have studied electronics formally in college. Instead, I chose chemical engineering, and as a result my understanding of electronics remained mostly informal and self-taught. I learned what many components did and occasionally managed to make circuits work, but I never developed the systematic foundation that comes from studying the subject in a structured way.
Recently I decided to return to this long-standing interest and learn electronics more thoroughly, beginning with the fundamentals and building upward in an organized way. As I worked through several books, I quickly rediscovered something important: reading alone is never enough. Real understanding comes from building circuits, taking measurements, and seeing firsthand what actually happens. So alongside my reading, I began doing small experiments at the workbench—simple circuits, basic measurements, and little investigations using a breadboard and a digital multimeter.
These posts are essentially my bench notes. They follow my progress as I study and document the experiments I use to reinforce what I am learning. Rather than presenting formal lab reports, I’ve chosen a more workshop-style approach. My hope is that someone else could follow along, build the same circuits, and repeat the same measurements if they wished. Each post will introduce a concept, construct a simple demonstration circuit, and explore the results through measurement and observation.
This approach also reflects something I discovered during my years of teaching: I often learned a subject best when I tried to explain it to someone else. Teaching forces you to organize your thinking and clarify ideas that may otherwise remain vague. In that sense, these notes serve two purposes at once. They help me deepen and organize my own understanding, and they may also prove useful to others who are curious about electricity and simple electronic circuits.
Everything here will be simple, practical, and hands-on. We’ll begin with the basics—measuring voltage, current, and resistance—and gradually work toward small but meaningful circuits that we can build, analyze, and understand.