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 ...

Or just use a MOSFET if the relay isn't very fussy. Or, use a combination of the Arduino driving something like the above timer relay, which itself will pull the 12V relay high if that's all it needs.

Magnetic tape storage is something many of us will associate with 8-bit microcomputers or 1960s mainframe computers, but it still has a place in the modern data center for long-term backups. It&#82… ...