michael from the friday-night-build-your-own-series-continues dept.
edBX writes "GideonTech.com has a new guide up on how to make your own electronic lock using a key card. Built using a phototransistor, infrared-emitting diode and a few ICs, they are able to turn on their computer using a punched out phone card."
It is contrary to reasoning to say that there is a vacuum or space in
which there is absolutely nothing.