On Wed, 26 Nov 2008 11:41:04 -0800 (PST), Richard Fry
wrote:

Hopefully you or Richard Clark can tell me the reason(s) for this
difference, which could easily be my own setup of the NEC model.

I modeled their structures as they built them explicitly (they had
many variations), at the frequency they used, took readings at the
distance they reported. For your 1 kilometer distance (not one they
used), I get 303 mV/m at 3 MHz for their 70 foot radiator over a field
of 113 x 135 foot radials with an average ground conductivity. When I
use their distance of a mile, I get 188 mV/m, all else identical.
Their paper reports by formula that I should see 194.5 mV/m.

It would appear that with the average of the two distances, my model
accords quite closely to BL&E. That average would suggest results are
within an unreasonable accuracy given my experience with making RF
power determinations at the bench. However, my model is repeatable,
the paper is chiseled into the granite of history and your original
complaint seems to be moot.

73's
Richard Clark, KB7QHC