Basic Electronics for Beginners in 20 Steps

Step 17: Your First Circuit

Parts List:

• 1K ohm - 1/4 Watt resistor
• 5mm red LED
• SPST toggle switch
• 9V battery connector

In the schematic, the 1K resistor, LED, and switch are all wired in series with the 9V battery. Once the circuit is built, the LED will light up when the switch is on and turn off when the switch is off.

You can use a graphical resistance calculator to find the color code for the 1K resistor. Also, remember that the LED must be inserted correctly— the long leg connects to the positive side of the circuit.

You may need to solder solid core wire to the legs of the switch. If soldering is too tricky, you can skip the switch.

Once built, flip the switch to see how it works!