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Total posts : 45366Can we just say 12 nW?
Total posts : 45366Carl from Ferguson said: “Can we just say 12 nW?”
John and the Resident Hobby Agent said: “That would no longer be functionally compliant.”
Total posts : 45366Per NEC4.2 analysis:
1) A power of 11.48… nW radiated by a matched, 1/2-wave dipole into free space produces a maximum field intensity of 250 µV/m at a distance of 3 meters from the transmit antenna. This exactly meets FCC §15.239.
2) If that same setup is installed so that its dipole is vertical, and with its radiation center 10 meters above level earth having 5 mS/m d.c. 13 conductivity (average), then for a carrier frequency of 99.9 MHz its maximum field intensity at 3 meters would rise to about 393 µV/m — due to the presence of earth reflections.
3) If it is installed using different frequencies with different heights/different polarizations/different antenna types/different earth conductivities, then the answers will be different than in 2) above.
So as in many cases, a simple question or set of assumptions does not mean that the (accurate) answer will be simple, or apply to all conditions.
An inaccurate conclusion can be stated with great precision, but it is still an inaccurate conclusion.
Total posts : 45366One seeks to apprehend the Rules so as to comprehend them.
The foregoing lesson on distinquishing between precision and accuracy serves the latter and contributes toward critical thinking as as a tool for both.
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