20 hands-on builds

Simple, correct, low-part-count circuits you actually build — starting from a single LED and working up to transistor switches, relays, timers, and troubleshooting. Pairs well with the main 40-lesson course, but you can start here directly if you already know the basics.

• 01 — Planning Your Circuit Before You Build (Getting Started)
• 02 — Building a Simple LED Circuit (LEDs & Resistors)
• 03 — Building a Series LED Circuit (LEDs & Resistors)
• 04 — Building a Parallel LED Circuit (LEDs & Resistors)
• 05 — Building a Switch-Controlled Circuit (Switching)
• 06 — Building a Voltage Divider Circuit (Voltage Dividers)
• 07 — Building a Potentiometer Dimmer Circuit (Voltage Dividers)
• 08 — Building a Pull-Up / Pull-Down Resistor Circuit (Switching)
• 09 — Building a Simple RC Timing Circuit (Timing)
• 10 — Building a Transistor Switch Circuit (Switching)
• 11 — Building a Relay-Controlled Circuit (Switching)
• 12 — Building a Simple LDR Sensor Circuit (Sensors)
• 13 — Building a Simple Buzzer Alarm Circuit (Alarms & Alerts)
• 14 — Building a Battery Pack: Series & Parallel Cells (Power)
• 15 — Building a Fuse-Protected Circuit (Protection)
• 16 — Building a Status Indicator Circuit (Indicators)
• 17 — Building a Push-Button Latch Circuit (Switching)
• 18 — Building a Simple Transistor Audio Amplifier (Amplification)
• 19 — Combining Series & Parallel in One Circuit (Foundations)
• 20 — Troubleshooting a Circuit That Doesn't Work (Troubleshooting)