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Old 12-28-2017, 12:07 AM
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The 5% or 10% longer for ground radials is an old myth, they should be 1/4 wavelength resonant if possible. That provides an exact 1/2 wavelength round trip from the feedpoint to the end of the ground radial and back to the feedpoint, mimicking the feedpoint impedance.

Originally Posted by MOTEX View Post
For VHF, you will need at least 20 inches of ground plane in all directions since ground planes must be at least 10% larger than 1\4
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