An electronic device would now help trace remote controls of televisions, audio systems and satellite receivers in case these are misplaced. Researchers in the UK have developed the device which emits a signal to enable the user to locate the missing handset. A very small key finder circuit comprising a microphone, a special integrated circuit (IC), an amplifier and a small battery, is placed inside the remote control. The microphone being a piezoelectric element -- that can convert mechanical or acoustic signals to electric signals -- also functions as a loudspeaker. The device responds to the whistle signal of the user and enables him to locate the misplaced object.