JPC-12 7MHz-50MHz 100W Multi Band HF Shortwave GP Antenna QRP For Ham Radio. Mini HIFI Headphone Amplifier 3.5mm Portable AUX Audio w/ USB Cable Earphone AS. Rolling power: 100w. To lengthen the rod antenna or increase the number of turns of the loading coil, if the resonance frequency is low, shorten the antenna of the rod antenna or reduce the number of turns of the loading coil.
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