Tag Archives: LED

This is why you always put a 1kΩ resistor in series with an LED

It’s always a good idea to wire a 1kΩ resistor in series with any LEDs you use in order to limit the current, and this is why:

Usually the resistor just burns out, but this LED was entirely different – it split right in half! I’m still not quite sure why, but Occam’s Razor states that it’s more likely to be a manufacturing defect rather than some new phenomenon.

Thanks to my colleague PAS for bringing this to my attention.

LED throwies

Here’s a project for half-term: magnetic LED throwies.

The Finished Article

First you’ll need an LED. You can buy them from any electronics supplier such as Maplin, Rapid or RS.

You’ll also need a small magnet. I bought 12mm×2mm neodymium-boron magnets from first4magnets.com.

Lastly you’ll need a CR2032 battery. I bought mine from cheaperbatteries.co.uk.

Step 1: Place the battery in between the “prongs” of the LED.

Step 2: Attach the magnet to the battery and LED.

Step 3: Wrap the whole thing in electrician’s insulating tape, available from any DIY shop.

Step 4:

Props to Graffiti Research Labs for the original idea.