Patent ID: 8001699

Claim:
A device comprising: a housing including a connector for connection to electronic circuitry, the housing securing a key decoder with a portion extended therefrom; the key decoder containing a single longitudinal groove along at least a portion of the key decoder and divergent sloping surfaces at the end of the extended portion: a conductor positioned in the single longitudinal groove that is insulated except for an exposed portion at the end of the conductor which serves as a reader; an electrical measuring device secured to the housing and connected to the conductor for providing electrical signals to the electronic circuitry from the reader when the key decoder is in contact with and out of contact with a wafer tumbler in a lock, where the electrical signals correspond to the distance the reader has traveled within the lock from the entrance of the lock as the key decoder is urged in through the lock and a processor included in the electronic circuitry responsive to the electrical signals for mathematically determining cuts to be made in a key based on the electrical signals, the cuts representative of the positions of the wafer tumblers along a keyway of the lock for fabrication of a replacement key.