Time Delay Relay Schematic: http://goo.gl/Ss21x
3 TRANSPONDER RFID KEY for $18 with S+H: http://goo.gl/RMIZE
Basically it's a 27 seconds time delay relay, RFID tag system, project box from Radio Shack, some wire and heat shrink.
if you have any questions let me know.
Schematic with RFID and Time Delay Relay http://goo.gl/sv7bG in .PDF
Technical problems with RFID: http://goo.gl/B5k4h
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