It uses a very high Q Spider Coil. The coil is wound with 660/46 Litz and the Q is in excess of 1000, too high to measure on my HP 4342A Q Meter. The radio has only one tuned circuit, the spider coil using a "Holy Grail" silver and ceramic variable capacitor. The antenna is coupled to the spider coil with the smaller non-resonant spider coil. This coil does not resonate anywhere in the broadcast band, if it it did it would try to inject stations at its resonant point.