JPC-12 7MHz-50MHz 100W Multi Band HF Shortwave GP Antenna QRP For Ham Radio. The shrinkage length is about 34.5cm, and the erection length is about 410cm. 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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