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 ...

I just received my RC522 RFID reader and made this simple Arduino access control system that uses the reader, a buzzer for the alarm and a relay shield for the security system. The relay can be used ...

To be specific, it isn't an Arduino brand, it is a DigiSpark, but the trouble isn't with the device itself. The problem is with a buzzer ... this circuit to drive a relay (like if you want ...

Once the timer countdown reaches 0 seconds, the PIEZO-BUZZER (BZ1) will bang on and the LCD display will blink “TIMER ALERT!”. An optional RELAY driver output is available at pin 4 of the Arduino ...

Since [Chuck] only had a short bit of time and a tiny budget to work on, he opted to find the easiest solution to the problem, which was an Arduino-based game show buzzer system. The game display ...

Inside the cool laser-cut box is an Arduino Uno and a 9V battery, plus a current-limiting resistor and the all-important buzzer. We like how [newsonator] wired up the LEDs to the Arduino by ...