It all started with a small LCD salvaged from an old printer. I recruited my code-savvy older brother, Adam, and we soon had the LCD displaying text from an Arduino microcontroller. This was neat, but it was inconvenient having to plug the Arduino into a computer for reprogramming whenever we wanted to change the text. […]
This project uses a simple 555 timer chip and a feedback loop to control a servo-controlled wooden arm. Whenever an object comes close to a photosensor mounted on the end of the arm, it blocks the amount of light detected, which triggers the arm to swat the object away.
This project uses simple electronics to create an alarm circuit for a shoulder bag. The key components are two 1/8″ headphone jacks with “normally closed” switches, which detect whether a plug is in the jack. Wiring two of these jacks in series with an alarm creates a circuit that activates when both plugs are removed. […]
Jim Chen designed an excellent electronic “Whack-a-Mole” game using 555 timers, LEDs, and bent-diode touch sensors, that you can build on a solderless breadboard
Talk in secret over your own private laser beam link.
Powering a TV remote with the sun means you won’t have to buy batteries every six months to surf from your sofa. Low-voltage devices that use power only occasionally, like remotes, are good candidates for a solar-powered trickle-charge. Here’s how we modded our remote to live off of the sun, using rechargeable batteries connected in parallel with a small solar cell and a diode to keep any power from trickling back out.
By Sean M. Montgomery and Ira M. Laefsky Excerpted from a Primer on Biosensing in MAKE Volume 26. When you experience an arousing stimulus, like an evocative question, a startling noise, or even a disturbing thought, your body generates a variety of psychophysical responses. One of these is micro-pulses of sweat released after a 1- […]
