Two rows of coil inductors represent two separated loops of loop antenna. Voltage source shows sound and not AM carrier frequency (added to run in simulator). The right two capacitors are variable gang tuned capacitors to adjust one side of loop antenna through AM band.
Left loop is inductively coupled to tuned loop and goes to 3.5 mm jack for wire connection output if you wish. YouTube videos show adding a 1N34A diode in 3.5 mm jack circuit and connect to amplifier to make an AM radio. If using AM radio close by no connection is necessary.
With strong AM signal I do not find much improvement. For weak AM signal turn radio with build in antenna to strongest sound. Next place AM loop antenna close by or on top of radio to complement built in antenna. Lastly, tune variable capacitor on loop antenna to bring in strongest signal and clear up transmission signal.
Remember the old time radio whistling sound when two radio local oscillators were tuned close to frequency? A signal you may hear when fine tuning the loop frequency.
