So you want to learn about electronics! Good for you! The sky is the limit when it comes to this field, but let’s start with a very simple circuit.
Lighting up a light emitting diode (LED).
The entire circuit is very simple — it consists of an LED, a power source (batteries), and a resistor to limit the current through the LED.
Light emitting diodes will emit light when a voltage is applied to them and current flows through them. Different colors and types of LEDs may require different voltages and currents, but a standard red LED requires 1.7 volts and .02 amps (20 milliamps, or 20 mA).
Here is a how to build your circuit if you’re a very beginner without many tools yet.
I have two AA batteries (1.5 volts each) that are connected in series to make about 3 volts. (Click here to learn about series connections.)
They are in a little battery holder with alligator clips that I soldered on to make the connections easier.connected to the LED and a current-limiting resistor.
I used an extra alligator clip to connect the resistor to the LED. You could use a paper clip, or just wind them together.
Here is what the circuit looks like in a schematic diagram:
Even this simple circuit needs a little forethought.