Just don't expect a 6 transistor pocket radio to provide excellent reception if the distant station is near strong local stations - the selectivity and automatic volume control of the inexpensive receiver may not be up to the task. These small loop antennas can turn radios with poor sensitivities into modest DX rigs. Terk manufactures such a product - an 8 inch circular loop with a tuning capacitor embedded in the base. Even 8 inch loop antennas, however, may have high gain. This is not necessary in many cases, all you have to do is get the radio within a few inche of the loop to couple the signal from the antenna.Īs nice as loop antennas are, there are some limitations you might want to consider before considering one: A sense winding may be included that provides electrical connection to a radio's external antenna jacks. The inductive winding consists of a primary, which forms a resonant network with the tuning capacitor. It consists of an inductive winding and a tuning capacitor. The schematic diagram of an AM loop antenna is shown below. The physics of resonance allows it to have substantial gain, even though it is comprised of passive components! The 'loop' part of the antenna is the inductor, and the tuning capacitor makes it resonate at a desired frequency. Requiring no power, it takes advantage of the resonant properties of an inductor and a capacitor connected in parallel to receive weak AM stations. She and her mother recently visited, and were impressed when this loop's little brother (also described below) was able to vastly improve very weak reception from a distant station on an average radio.Īn AM loop antenna is one of the true marvels of electronics. Erin Sanders, who played the part of teenage inventor Quinn Pensky on Nickelodeon's 'Zoey 101' show, with the author.

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