That is why you must use an external power supply (Vcc) that is between 7 to 12 volts to power up the Arduino board and the transistor + relay. The load uses its own power supply, for instance if you ...

Hi, I'm Bill. I'm a software developer with a passion for making and electronics. I do a lot of things and here is where I ...

In his garage, the Arduino and a set of relay systems connect to the circuits that control his sprinkler system valves. The Arduino is also connected to the Internet via Ethernet. The Android app ...

It’s a fairly simple project, too: just hook an Arduino Uno up to a motion sensor and an electronic switch called a relay, then plug in your fan, and you’re good to go. If that sounds ...