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All antennas in this thread are designed for ADS-B frequency 1090 MHz.

At this frequency, the wavelength is 275 mm.

These are 1/4 wavelength antennas, and length of elements (whip, radials, and can height) are 1/4 wavelength = 275 mm/4 = 69 mm

If you want to make these antennas for other frequencies, calculate length of elements (whip, radials, can height) by following formula:

Wavelength in mm = 300,000/frequency in MHz

Length of elements (whip, radials, can height) = 1/4 x wavelength

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