Practical Electronics & Arduino: Learn Circuits by Building Them — from Ohm's Law to Sensors, Motors, Bluetooth, Wi-Fi, Cellular and Your Own Printed Circuit Board

Practical Electronics & Arduino takes you from "what is a volt?" to designing your own connected device on a custom printed circuit board. Every chapter follows the same loop: the idea in plain words, a circuit you wire yourself, numbers you check with a multimeter or oscilloscope, and an Arduino sketch that reads or drives it. School algebra is all the math you need, and every formula comes with a worked example in real numbers.

Built around the Arduino UNO R4 WiFi and R4 Minima, with notes for the classic UNO R3 and its clones, plus the ESP32 and Raspberry Pi Pico 2 for wireless and low-power projects.

INSIDE YOU WILL LEARN

- DC circuits: voltage, current, resistance, Ohm's law, power, series and parallel networks, Kirchhoff's laws, Thévenin equivalents, voltage dividers and batteries

- Capacitors, inductors, AC, impedance and filters, with the oscilloscope, signal generator and logic analyzer

- Semiconductors: diodes, LEDs, bipolar transistors, MOSFETs, op-amps, comparators, the 555 timer and power supplies from linear regulators to buck and boost converters

- Digital logic, shift registers, 3.3 V and 5 V level shifting, and what really happens inside a microcontroller

- Arduino programming in C++: digital and analog I/O, the R4's 14-bit ADC and true DAC, interrupts, timers, non-blocking code, state machines, serial debugging, EEPROM and writing your own libraries

- Sensors: temperature, humidity, pressure, true CO2, particulates, distance (ultrasonic and time-of-flight), motion, IMUs, load cells, current and power, with I2C, SPI, UART, 1-Wire and Qwiic

- Outputs: LCD, OLED, TFT and e-paper displays, addressable LEDs, sound, DC motors and H-bridges, servos, steppers with the TMC2209, relays and safe switching

- Connectivity in depth: Bluetooth Low Energy (phone and Web Bluetooth control), Wi-Fi (web servers, HTTPS, JSON, ESP-NOW), cellular data with a SIM card (LTE-M, NB-IoT and Cat-1 modems, AT commands, SMS and MQTT), Arduino Cloud and Home Assistant

- Building real devices: soldering, stripboard, designing and ordering a PCB in KiCad 10, troubleshooting, low-power design, other boards and edge AI with TinyML

PROJECTS THAT PULL IT TOGETHER

An Arduino voltmeter and battery tester, a smart LED lamp with current monitoring, a reaction-timer game, an indoor air-quality monitor, a two-wheel robot car with obstacle avoidance and line following, a smart garden controlled over Wi-Fi and Bluetooth, and a cellular GPS tracker with SMS alerts.

WHY THIS BOOK

- 160 complete Arduino sketches, every one compiled for the boards it names before printing

- Exact breadboard wiring diagrams and schematics for every build, so nothing is left to guesswork

- "If it doesn't work" boxes for the faults real builders meet, and notes on what changes between the UNO R4, UNO R3 and ESP32

- Up-to-date for late 2026, including the UNO R4's 8 mA pin limit, the Zephyr core and Arduino under Qualcomm

- A summary and exercises at the end of every chapter, with answers at the back

- Written for readers worldwide, with US suppliers, US carriers and FCC rules first

Whether you are a complete beginner, a student, a teacher looking for projects that work, or a hobbyist ready to understand why your circuits behave the way they do, this book will give you the confidence to design and build electronics of your own.