A heat sensor activated detector having a housing, which accommodates a heat sensor, a logic device that compares the heat signal read by the heat sensor to a predetermined level and transmits an enable signal to an audible signal generator where the heat signal is outside of the predetermined level, an audible signal generator, and a power source. The heat sensor may be tuned to the body heat of the user. Also, the predetermined level may be set to a specific distance, such as three meters. Further, the detector may be attached, temporarily or permanently, to an object the user wants to protect against loss or misplacement.