Jim K9YC referred to the "slope of the decay of field strength" method
utilising the SLOPE of data compared to FCC curves.
As has been pointed out, this removes a number of variables but is difficult
and time consuming. However as a local broadcast station has to generate
data over a large area, this data might be useful for averaged far field
area ground conductivity which is what I believe the original question was
about. It appears that the IRU uses conductivity values determined by area
geological conditions.
I have not been able to locate these FCC curves (and it appears that they
may have been withdrawn). It would be interesting to know how the FCC curves
were derived in the first place as it assumes that someone had extensive
area ground conductivity information.
73 Keith VE7MID
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Remember the PreStew coming on October 20th. http://www.kkn.net/stew for more
info.
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