Here's a fantastic Great Circle Map program that will allow you to position your antenna direction for DX contacts to amateur radio stations anywhere around the world.

It is also useful for shortwave listening. Shown here is the short path (red) and long path (black) and distances of the path lengths between Adelaide, South Australia and England. Day and night zones are shown giving you an idea of frequencies (day or night) to choose for a DX contact long or short path.

For a simple dipole wire antenna running North/South you can work out the half power beam width of the dipole lobes into North America and Europe.

For beam antennas such as Yagis and Quads this will give you accurate beam headings.

Download from: www.qsl.net/w6elprop/  Thanks Sheldon W6EL for a great program.

ANTENNA HEIGHT:

Remember if you are using horizontal antennas, the height of the antenna above ground has a large effect on the radiation pattern.

You need to get as much energy as you can going in the direction you want, and receive as much signal as you can and not be haphazard.

http://www.ve3sqb.com/hamaerials/aa3rl/