- Ohms Law
- Series vs Parallel
- Full-wave Rectifier Explanation Shows how it works.
- EEVblog David Jones' video blog - lots of tutorials and interesting stuff.
- Hexadecimal Numbers Explains how the hexadecimal (hex for short) number system works.
- Phase Control Explains how phase control is used to dim AC lights.
- Volts Amps Watts Very Simple Power Calculator.
- Using a transistor as a switch Tutorial
- using a MOSFET as a switch Tutorial
- LED Series Resistors
- Voltage Dividers (Doctronics UK)
- Soldering made easy
- Soldering 101 (Sparkfun)
- Soldering SMD (Sparkfun)
- Surface Mount Soldering 101 (CuriousInventor)
- SMD Removal using a ChipQuik kit
- Professional SMT Soldering: Hand Soldering Techniques
- Soldering wires together
- Soldering wires together - interleaved method
- Soldering wires together - butt method
- Soldering components on PCB
- Electronic Components
- Resistor Colour Codes
- SMD Component Markings
- Wire Sizes
- Connector Pinouts
- Connector Types
- PCB trace width calculator
- Battery Life Calculator
- Parallel Resistance Calculator
Measurement & Tools
- Using a multimeter (Doctronics UK)
- How to use a multimeter (wikiHow)
- Using an oscilloscope (Doctronics UK)
- Basic 1X and 10X Oscilloscope Probe Tutorial
- Logic Probe Basics (WISC Online)
- Tools required for DIY