This is a hotel room door swinging open. The device he holds in his hand is an Arduino connected to the OUTSIDE portion of the door lock. It takes approximately 200 milliseconds from the time an ...

How the resistor color-code bands work At the heart of the project is an Arduino Nano clone and a potential divider that measures the resistance of the test resistor against a known fixed value.

Thankfully, the Arduino board is one of the most popular ... of frequently used hardware like basic electronics (e.g., ...

Save for the Arduino Nano, it requires pretty basic electronic components you might already have on hand, including three different colored LEDs (green, orange, and red), a 10k-ohm resistor ...