If you’ve worked with passive RFID before, you know that most ... 12 AA batteries and a custom PCB using an Arduino Nano to interpret the reader’s output. When the reader sees a nearby card ...

But his final iteration was to make a standalone reader with an Arduino and use WebUSB to connect ... He also decided against RFID but didn’t really say why. NFC business cards are a thing.

The project relies on the built-in Wi-Fi module of the Arduino Yun, and the microcontroller is connected to the sensors and RFID reader modules alongside an electronic strike to lock/unlock the door.

Also called an "RFID interrogator." The maximum distance between the reader's antenna and the tag vary, depending on application. Credit cards and ID badges have to be brought fairly close to the ...