Learn about how components such as resistors, capacitors, LDRs and so on work, look at circuit theory and how to use soldering tools. ## How Colour Changing LEDs Work

A colour changing LED contains a red, green and blue LED along with a small computer to drive them, but how do they work to produce different coloured light? Find out in this tutorial. ## How To Calculate Capacitors In Series And Parallel

Calculate the combined total capacitance of capacitors in parallel and series using the formula and explanations detailed in this tutorial. As well as explaining the formulas and maths involved there is also some tasks for you to test yourself for two and three capacitor networks. ## How to Calculate Resistors in Series and Parallel

Calculate the combined resistance of resistors in series or in parallel using the formulas and explanations described in this tutorial. As well as explaining the formulas and maths involved there is also some tasks for you to test yourself for two and three resistor networks. ## How To Calculate And Understand Resistor Values

The value of a resistor can be calculated using the colour bands on the resistors casing, find out what each colour means and how to read them with this tutorial. Resistor tolerances, a worked example, the resistor preferred value system and some tasks for you to try are also included. ## How an LDR (Light Dependent Resistor) Works

A light dependant resistor or LDR is a sensor that changes resistance as the light level changes, see example circuits and explanations in this tutorial. This tutorial also covers what an LDR looks like, the circuit symbol, typical resistances for different light levels and some example applications. ## How to clean and maintain your soldering iron - Kitronik University

Over time soldering iron tips accumulate old solder and other debris, this guide shows how best to clean the tip with a damp sponge or tip tinner / cleaner. There is an accompanying video tutorial, the tip cleaning guide is just part of wider collection of tutorials on using soldering irons.