Tools
How to remove VAT from a price using a calculator.
Take VAT off a price on any calculator or in your head: divide by 1.2 for the UK rate, with the reasoning and a worked example.
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Electronics
Charging Lithium Cells with a Bench Power Supply
How to charge a lithium cell safely from a bench power supply: read the datasheet, set the voltage and current, and know when to stop.
Electronics
555 timer astable: flashing an LED on a breadboard
Wire a 555 timer in astable mode to flash an LED, with the frequency and duty cycle calculated for the parts used and a diagram to copy.
Electronics
Make a simple LED circuit on a breadboard. (Maths included)
Build a one-LED circuit on a breadboard and use Ohm's law to pick the right resistor, with the maths worked through step by step.
Electronics
Capacitors: What They Are and How They Work
What a capacitor is, how it stores energy, the main types and uses, and how to work out total capacitance in series and in parallel.
Programming
“Hello, world” Way too much information
The story behind the first program every coder writes, and Hello, World in sixteen languages from Python to x86 assembly.
Electronics
What are resistors & how do they work?
What a resistor does, Ohm's law, colour codes and materials, with worked examples of a voltage divider and choosing a resistor for an LED.
Technology
Do You Really Need to ‘Safely Remove’ USB Drives?
Why the safely remove prompt exists, when pulling a USB drive out is harmless, and when it can corrupt your files.
Technology
Are files really gone when you click delete?
Clicking delete does not wipe a file. What actually happens on your drive, why overwriting is the only real erase, and how to do it properly.
Technology
Is ‘www’ Needed Anymore?
Where the www prefix came from, why most websites no longer need it, and whether it still matters for yours.