I, Screechy
A light-sensitive oscillator toy.
9V battery
The Stalker ‘Bot
Gather the parts and follow the basic instructions and you can have a robot capable of following moving objects! With basic coding experience, you can also change the distance at which the robot senses moving objects or the speed the robot moves. In order to do this project, a basic robot must be built that […]
Hear with Ultrasound Using a TL494 as a Flanagan Neurophone
Patrick Flanagan invented the “Neurophone” over 40 years ago. His original patent (US3393279) was basically a radio transmitter that could be picked up by the human nervous system. It modulated a one-watt 40kHz transmitter with the audio signal, and used very near-field antennas to couple it to the body. It also used extremely high voltages. […]
MonoBox Powered Speaker
Learn how to build inexpensive powered speakers that amplify the output of your headphone music player. It may be small, but this speaker can still rock!
Shake-Activated Present Prank
At the heart of this project is the Radio Shack 9V Recording Module. This device records and plays back up to 20 seconds of sound. In this project I show how to modify it to make it motion sensitive.
Evasive Beeping Thing
The Evasive Beeping Thing is appropriately named, since it dutifully does exactly what its name implies: it sends out a 5-second, high-pitched beep every few minutes. The source is extremely difficult to locate because of the way that high frequencies can penetrate objects and trick our ears. You’ve probably encountered something similar in the real […]
Talking Booby Trap
People snatching your top-secret stuff? Here’s a sneaky gizmo to keep those snoops away.
