Approximately One wavelength of height will greatly improve the local & distance signals.I think that's around 38 feet or so.I have been running my FREE Antron 99 at just 30 Feet for about 10 years & I have worked the world on 10,11,12,15,& 17 meters.Some will Poor Mouth them but they still perform so I'm keeping mine until it no longer works.It has survived several Florida Hurricanes,many Thunder storms,a few hail storms,& an Ice Storm.It's a tough antenna & I work everyone that I hear on it.Also there is only ONE SWR = Standing Wave Ratio & no SWR's = Standing Wave Ratios.. {:>)
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