Looking to get into the world of electronics? While it’s always worth learning the theory – including Ohm’s law, how a capacity works, and how voltage is different from current – you’ll tend to enjoy the hobby a great deal more if you can build practical circuitry, right away.

Let’s take a look at five different circuits that you can build with only a few choice components.

LED Flasher Circuit

Making an LED blink is easy when you have a programmable microprocessor – but you can do it with the help of a few resistors, transistors, and capacitors, too. The capacitors fill up and discharge repeatedly, depending on their size (and the value of the resistors you’ve chosen). While this might not be quite as flexible as a programmed solution, it will acquaint you with vital principles and components, which you can then employ in your own designs.

Light-Activated Switch Circuit

This circuit relies on an LDR (that’s Light Dependent Resistor). These change their resistance based on the available ambient light – which makes them great for dimming lights and bringing them back up at night time. You can use a transistor to make the LDR work with a higher-voltage circuit. The signal from the LDR can be fed into the transistor, which in turn can control the strength of the signal going into a light bulb.

Simple Audio Amplifier Circuit

If you’d like to ultimately build synthesizers, guitar pedals, or other musical equipment, then getting to grips with op-amps and how they work is vital. This simple circuit pairs the op-amp IC with capacitors and resistors, stepping up weaker signals so that they can be played on headphones or loudspeakers.

It’s worth noting that the use of headphones in circuit design imposes a little bit of risk – make sure that you’re not going to deafen yourself by buying a small speaker for testing purposes.

Battery Level Indicator Circuit

For getting to grips with voltage, building a battery indicator circuit can be hugely instructive. All you need is a few resistors and LEDs, which you’ll arrange in a ladder. The more capacity there is in the battery, the more LEDs will light up. This removes the need for analog ammeters – though these are still worth having, to check whether your display works properly!

Touch Sensor Circuit

Capacitive touch sensitivity is a vital part of the modern world. It’s what allows the touchscreen on your smartphone or tablet device to work properly. Of course, you needn’t build anything quite that sophisticated just yet. You can get a capacitive touch sensor working with just a 555 timer, some resistors, and a transistor. The IC can detect the small changes in capacitance that occur when your finger (or any other conductive object) is placed across the sensor.