Guy Olinger wrote:
>BL&E gave their study conductivity limits as between 20 and 100
>milli-Siemens !!!
Those who believe so might want to review the conversion from the e.m.u.
units used for earth conductivity in the BL&E publication to the mS/m units
more commonly used today.
--> The conductivity values used by BL&E as quoted above are overstated by a
factor of ten. <--
Other details that may have been overlooked or forgotten:
- The BL&E tests were conducted in the sandy soil of New Jersey, where
according the FCC M3 chart of earth conductivities, that state ranges from 2
mS/m to 4 mS/m.
- Field intensities were measured by BL&E at a distance of 3/10 of mile from
the radiator, and mathematically converted to an equivalent IDF at 1 mile.
- The test frequency was 3 MHz.
- Even with such rather low earth conductivity at/near the BL&E test site,
the fields they measured for monopoles of ~45 degrees and more, using 113 x
0.412-wave buried radials were within several percent of the maximum fields
possible for the applied power when using perfect monopoles of those heights
driven against a perfect (zero loss) ground plane.
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
|