How to read the graph:
When the line goes wide there is propagation but not necessarily a man-made signal. The absolute value of the noise level is not important for propagation, but it is interesting to watch how the noise changes over time. Slow changes are usually made by the ionosphere (5min and longer). The slower the rise of the signal the further away it originated. Fast changes are man-made signals, hence vertical lines…
The black bottom graph is easier to read when it comes to propagation. The grayscale indicator shows propagation for all the bands according to color codes as in the sig/time graph. White is best propagation. |