The proposed broadband indoor active loop antenna increases the efficiency of reception of radio stations all LW bands (3-30 MHz) 3-5 times compared to telescopic.
Due to the fact that the loop antenna is sensitive to the magnetic component electromagnetic fields, electrical noise, caused by various household devices are significantly weakened.
Actually, the frame consists of 2-4 turns of insulated wire (diameter does not matter), arranged in the window frame (the author h cm, 3 coils).
A differential amplifier (T1, T2) has a gain of 10 dB up to 30 MHz, and the buffer T3 allows you to connect the output device to the input of the receiver is not only directly but also via 75 Ohm cable of any length.
Author: S. van Rudi