HF Propogation

The best frequency to use changes on an hourly basis depending on atmospheric effects and the range required.  The chart below can be used as a guide to this. 

Read across from the time of day (in UTC) and down from the range (in kilometres) desired and note the colour where the two lines cross.  The best frequency can then be found from the colour bar above or below the chart.

The chart is updated hourly - make sure you refresh your browser before using the chart.

Here's the six-hour prediction chart if you prefer it: