This tool calculates the antenna capacitance and radiation resistance of small vertical monopoles at 475 kHz. It is by no means a replacement for antenna design software such as EZNEC, but should give a clue how the antenna will perform.
Following limitations apply:
- Total dimension (H+L) less than 15% of the wavelength (= less than 95 m)
- Wire or small tube construction (less than 2.5 cm)
- The calculations assume an unobstructed antenna. Object near or under the antenna will reduce the radiation resistance and increase the antenna capacitance.
Visit the Calculator in 472kHz.org
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