Inductive loop radio receiver system for improved reception - is fitted with inductive and capacitive pick-ups for enhanced signal strength

摘要

The inductive loop receiver system overcomes the problems of reduced reception due to the position or orientation of the pick-up apparatus. The inductive loop (1) is a continuous one and is driven by a very low frequency between 16 KHz. The receiver (5) employs a conventional pick-up coil (7) tuned by a capacitor (8). Additionally, the receiver has a metal capacitance plate which with the self-capacitance of the user (10) forms a capacitive coupling with the electric field of the radiating loop. A very small order of capacitance (17) connects the input to an amplifier whose output is connected in parallel with the load of the first tuned circuit (6). The capacitive pick-up circuit can employ a FET connected in source-follower mode.