There is little propagation to report again this week but, half way through the week, there was a sunspot. OK, it was only a tiny one and it disappeared almost as soon as it came but it did belong to the new cycle so there is hope yet.
The Earth passed through a strong solar wind, the result of the output from a coronal hole but there was little listening disturbance.
Continuing with this informal look at the science of propagation we move on ever upwards to look at the concentrations of electrons in the upper atmosphere.
As you rise up above the earth you pass through the layer in which our weather exists and, above this, there are various other layers named with letters of the alphabet.
The layers
Each layer is a concentration of ionisation and most of them simply reduce the power of signals that pass through.
However the F layer is different. Splitting into two during the day, the F2 or highest of the F layers, is the one responsible for most of the serious DX on our planet.
Put simply, signals travelling upwards hit that layer and are returned to Earth to be received sometimes on the other side of the world.
F2 'weather'
But the F2 layer is not like a mirror that reflects everything it receives. The concentration of ionisation is patchy, some parts are dense and some parts not so and these patches change constantly in a pattern that is somewhat like the terrestrial weather systems we all experience.
This is what makes DXing such a variable art. At times the layer will reflect many of the signals that are received while at others DX is almost none existent. At the same time, the conditions can change quickly across the planet and local DX can appear, only to disappear a short time later.
It really a case of looking up there and seeing what the layer is doing today!
Sunspots
However there are patterns that do exist and next time we will look at the effect of sunspots and sun cycles on F2 propagation and why it is so poor today.
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