Photos of my 40 through 10 meter Fan Dipole



 

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Some basic antenna info

  Antenna thoughts August 2025 If one knows the basics of antennas then it becomes easy to choose what antenna is best for you. There is no one “best” antenna. There are very good antennas of course but even a very good antenna is not going to be right for all uses. I will discuss some antenna basics here and give some “rule of thumb” guidelines on how to think about antennas.  The halfwave dipole can be considered the basic building block of antennas. I think understanding the dipole is the key to understanding antennas. Also for antennas we need to think in terms of wavelength, not feet or meters.  For example a dipole 1/2 wavelength long and 1/2 wavelength high above ground is an excellent antenna. It has a gain of about 8dBi off the broadsides. It has a slight reduction in signal strength off the two ends. It’s peak radiation ( off the sides) is centered at about 30 degrees. The actual radiation is rather broad from about 15 to 45 degrees and gradually drops off above...
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Antenna Gain, dBi, and Radiation Angle tidbits

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Radiation from an antenna

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