[BC] WLW Superpower Coverage

[Richard Fry]

Robert Meuser post #1:

I am not sure how Richard is calculating this, but the FCC charts will
not take you out that far for the ground conductiviy given. The chart
bottoms at about 800 KM for that ground conductivity.

R Fry response to the above:

The current FCC charts for 700 kHz* are shown for 1 kW of radiated
power, and bottom out at around 850 km (528 miles) for 10 mS/m
paths.  That is within the range of my earlier post, and needing only
to be adjusted for the power difference.

  * http://www.fcc.gov/fcc-bin/73184?type=1&no=6

Robert Meuser post #2

Well I guess since we're going off the end of the chart and blowing up
software, we might never find out unless maybe the EBU or ITU have
something that handles higher power.
_____________

Rob, we're not going off the end of the chart for 500 kW ERP, a 10 mS/m 
path, and a 195 degree omni vertical.

The FCC charts DO cover MORE than the field strengths and ranges for which 
you first posted an (erroneous) objection, when adjustments are made for 
the difference between the 1 kW tx power for which field strengths and 
distances are shown in the FCC charts, and the tx power actually used 
(which is SOP).  That carries us to at least 500 megawatts.

And if 500 megawatts won't get us beyond 661 miles of 700 kHz, 0.1 mV/m 
groundwave (non skywave) coverage over a 10 mS/m path, why should we be 
concerned that FCC curves or software don't carry us further?

What's the point?  No combination of tx power and (even directional) 
antenna gain can produce that much groundwave ERP at 700 kHz in the first 
place.

RF