Illustrating long distance skip on 20m!

Have a look at this propagation on Reverse Beacon Network. My CQ call in CW has been picked up by reverse beacon network at a distance of 3263 miles with a signal to noise ratio of 20 dB, while it has been picked up at a distance of 171 miles at just 8 dB. This is quite usual on 20m, when nearby stations are not heard very loud or not at all while long distance stations are heard better. That is why 20m is a popular band for long distance or DX communications in amateur radio. Part of the difference could also be explained by some directivity of my multi-band inverted V fan dipole antenna.

My antenna orientation is approximately East-West so that propagation to the North along the broad side of the antenna is likely to be better than to the North-East for the nearer station. This simple graphics from RBN illustrates two wonderful principles of propagation of radio waves. For those not familiar with Reverse Beacon Network, it is a network of automatic stations skimming callsigns from CQ calls and posting them to the website online. It is very useful to study the propagation of amateur radio signals of your station on various bands and at different times of the day.