Art Unwin wrote:
"Richard`s response to the "error" question totally ignored TOA saying
they are usually the same."

Propagation dictates the take off angle that the signal actually follows
regardless of what your antennas do. We made meadurements on different
days so that propagation may have been different on different days. We
were checking over nearly the actual paths under what might be typical
conditions. Did the curtain produce louder signals? You bet!

Even though the curtain antenna had sharper vertical directivity as well
as sharper horizontal directivity than the lone dipole, these were the
goals of the design. Produce more signal on target to try to overcome
the myriad of jammers that were trying to drown us out.

During our tests, the paths between transmitter and the receivers were
the same in most cases. The width of a curtain was only about one
wavelength and the dipole was immediately adjacent to the curtain. The
curtain was two dipoles high, two dipoles wide and two dipoles deep as I
recall. Those dipoles in front were all driven in phase. Those behind
were tuned parasitic reflectors. It wasn`t unique at all. I`ve seen many
since then which look very much like our curtains. They were well
behaved and brought in lots of fan mail. They obviously radiated ok. The
reflectors seemed to shield the villiage behind them from being drowned
in radio frequency energy.

Whatever differences there may have been between the conditions imposed
on the dipole and curtain, they were tuned and loaded for the same
transmitted power. Received signal differences were likely due to gain
in the curtain versus gain in the dipole. Averiging a large number of
samples likely straightened out inevitable minor differences. I would
wager our results were good enough.
My employer was satisfied and all the contractors got paid.

Best regards, Richard Harrison, KB5WZI