Banner
Variable Speed Fan With Snap Circuits, Kano Computer

In a previous How-To Guide I demonstrated how to blink a Snap Circuits LED with the Kano Computer...

IUPUI researchers use stem cells to identify cellular processes related to glaucoma

INDIANAPOLIS -- Using stem cells derived from human skin cells, researchers led by Jason Meyer...

Pi Day 2016 Project

For Pi Day 2016, I’ll demonstrate how to flash a Snap Circuits LED with the Kano Computer (my...

LIGO, Gravitational Waves, And Laser Interferometry

UPDATE: LIGO has detected gravitational waves. ...

In a previous article I wanted to know if I could use the recording medium from old floppy disk as an infrared (IR) filter to shoot infrared photography on an iPod. I built a simple IR detector using Snap Circuits to test how well the floppy disk would absorb visible light yet let infrared wavelengths pass through. In that circuit I used the photodiode Snap Circuits block (Infrared Receiver U24) as the infrared detector. Even though a photodiode was useful for building a simple IR detector, another electronic component that is often used to detect infrared light is the phototransistor.
The Science Play and Research Kit (SPARK) competition winners were announced today. The SPARK competition was a challenge to “reimagine the chemistry set for the 21st Century,” according to the Gordon and Betty Moore Foundation and Society for Science&the Public press release. Many people in STEM (Science Technology Engineering and Mathematics) careers today often recall being inspired by the chemistry sets of old that stimulated their curiosity, wonder, and interest in science. Sadly, many chemicals included in these old sets are now illegal and the newer sets, well, just don’t have the same kinds of thrilling experiments.
In a previous article I demonstrated an unbreakable code for secure communication through the United States Postal Service using One Time Pads created with Scrabble tiles (or Boggle cubes). It seems some clever folks at the University of Bristol have developed a method of quantum cryptography for cell phones.

Press release from University of Bristol 3 April 2014:

An ultra-high security scheme that could one day get quantum cryptography using Quantum Key Distribution into mobile devices has been developed and demonstrated by researchers from the University of Bristol’s Centre for Quantum Photonics (CQP) in collaboration with Nokia.

Occasionally I’ll come across a web page that shows you how to make an infrared (IR) filter for your iPhone (in my case the iPod Touch) out of an old floppy disk. I had an old floppy disk so I decided to see if it would actually work. The process is actually fairly simple: take apart a floppy disk, cut out enough of the disk (the Mylar and iron oxide recording medium) to cover camera lens, tape the piece of floppy disk over the lens, point your camera, and shoot your picture.

I actually did have an old floppy disk that I could use for this experiment:

In honor of the upcoming National Robotics Week (April 5-13, 2014), I’ve created “CockroachBot” based on my Snap Circuits programmable robot I designed for last year’s robotics week. CockroachBot will try to run away when it detects a particular level of light falling on its light dependent resistor. I designed CockroachBot to be easy to build completely out of Snap Circuits parts and easy to program to inspire folks from seven to centenarian to get interested in robotics.

There’s a popular YouTube video featuring mathematician Edward Frenkel where he describes how the NSA hacked our emails. It is a backdoor into the National Institute of Standards and Technology public key encryption standards.

I’ll borrow an analogy for a simplified description of how public key encryption works from Simon Singh. Imagine a sturdy metal box that can be locked shut with a padlock.