In this quick Arduino tutorial I will explain how you can control a relay using the Arduino Board, one 1K and one 10K resistors, 1 BC547 transistor, one 6V or 12V relay, one 1N4007 diode and a 12V fan ...

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 ...

[Allan Schwartz] decided to document his experience using Fritzing to design, fabricate, and test a custom Arduino shield PCB, and his step-by-step documentation makes the workflow very clear.

We peeked at the schematic and the shield is more for letting the Arduino control the radio by changing the oscillator frequency rather than performing the SDR functions. The IQ signals appear on ...