[Elecraft] On ground - in ground radials

[SteveL]

Several places I’ve seen the results of experiments conducted measuring vertical antenna radiated field strength as the number of ground radials were increased.  There is definitely a point beyond which the addition of more radials produces diminishing returns at increased expense and effort - and the number is around 40.  However, the number is very dependent on local soil conditions and radial length. 

References to several experiments...
https://www.antennasbyn6lf.com/files/160_m_vertical_measurements.pdf <https://www.antennasbyn6lf.com/files/160_m_vertical_measurements.pdf>

https://consumer.steppir.com/wp-content/uploads/2018/11/Radial-Systems-for-Elevated-and-Ground-Mounted-Antennas-2.2-12_2018.pdf <https://consumer.steppir.com/wp-content/uploads/2018/11/Radial-Systems-for-Elevated-and-Ground-Mounted-Antennas-2.2-12_2018.pdf>

The latter reference also compares and contrasts ground vs. elevated radials.  In short, you will require many more ground radials to match the performance of a few elevated radials.

Some good reading!
Steve
AA8AF

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> 120 radials was a legal requirement of FCC Rules, and was primarily for standardization of performance.
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