Exploring Electronics

Electronics is everywhere. The question is whether you understand it or just work around it.

This site teaches electronics from first principles — not just how to follow a wiring diagram, but why circuits are designed the way they are. Every concept is explained directly, grounded in real components and real numbers, so you can read a datasheet, design a circuit, and understand what's actually happening when you power something up.

Where Do You Start?

Articles are grouped into topics — the subjects of electronics, like circuit foundations and microcontrollers. Each article carries a difficulty tag (Beginner, Intermediate, Advanced) so you can gauge depth at a glance, but there's no paywall or tier to unlock — just start wherever your project and your questions are.

• New to electronics?

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  Start at the very beginning — no prior knowledge assumed.

  Start with What Is Electricity?

• Ready to build?

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  Pick up the physical tools alongside the Beginner articles whenever you're ready to wire something.

  Start with Breadboards

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Topics

Circuit Foundations

• What Is Electricity? — Voltage, current, and resistance from first principles
• Series and Parallel Circuits — How components connect changes everything about how a circuit behaves

Reading Circuits

• How to Read a Schematic — The symbols and rules for reading any circuit diagram

Components

• Resistor Color Codes — Decode any resistor's value and tolerance from its painted bands
• Temperature Sensors — How thermistors, analog ICs, and digital sensors each turn heat into a voltage
• Package Types — Through-hole vs. surface-mount, and why every part on this site plugs into a breadboard

Microcontrollers

• What Is an Arduino? — The board itself, and how to read a sketch's setup()/loop() structure
• Digital Pins — How a microcontroller drives an LED and reads a button, and why every pin needs a resistor
• Blink an LED — Build a single-LED circuit and flash your first sketch, end to end
• Pull-up and Pull-down Resistors — Why an unconnected input floats, and how a resistor gives it a reliable HIGH or LOW
• Reading an Analog Sensor — Wire a temperature sensor to an Arduino and read a continuous value with the ADC
• Building a Threshold Ladder — Turn one sensor reading into staged, at-a-glance LED output

Communication, Power (coming soon)

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Practical Tools

The physical tools used throughout the site — read these as you need them.

• Breadboards — How breadboards work internally, and the wiring mistakes that stop every beginner's first circuit
• arduino-cli — Compile and upload Arduino sketches from the terminal, no IDE required

Part of the BradPenney.io Network

This site is part of a family of progressive technical learning resources:

• Exploring Linux — Linux for developers and platform engineers
• Exploring Kubernetes — Kubernetes from first deployment to production clusters
• Exploring Python — Python automation for platform engineers
• Exploring Computer Science — CS theory for working engineers

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