In message <003701bfce1a$2a24f580$93fb88d4@w8k3f0>, Dick Rollema
<[email protected]> writes

To All from PA0SE

In an earlier e-mail I wrote:

>Computer program AO by Brian Beezley, K6STI, shows  for the L-antenna

over

>medium ground  an almost perfect omnidirectional radiation pattern. The
>deviation
>from a circle is no  more than about 0.1dB.

Mike Powell commented:

And yet did not Marconi use a vertical antenna with a long horizontal
wire to obtain directivity from Cape Race? When the original aerials
came down in a gale he found equal or stronger signal strengths using an
inverted 'L' with the arm pointing the right way.

Mike,

It depends on the length of the horizontal part af the antenna.

Jim used only 42m.

When the top is increased to 0.1 wavelength than a F/B-ratio of 2.23dB
results.

With a top of 0.25 wavelength F/B becomes 3.51dB.

Thanks, Dick

Considering the poor receivers in use at the time and the ratio of
vertical to horizontal (1:1?) I would have expected a bigger
improvement.

M.J.Powell