A number of government agencies around the world provide ionospheric predictions, such as vertical foF2 or oblique path useable frequency range advice. Examples include IPS, SWPC and DIAS. Typically, the major customers of these agencies are in aviation and maritime (for HF comms) and defence (for comms and radar).

Are these kinds of services used by amateur radio operators? If so, how useful are they (compared with having to operate without any such advice?).


1 Answer 1


As a (fairly) regular member of the Worked All Britain net on 40m, the foF2 (I use the Chiltern Ionogram) critical frequency is one that I watch carefully, as it gives a pretty reasonable indication as to whether inter-G contact (for the WAB squares) is possible.

Given that Chiltern can be temperamental, I do not rely on it, but it is certainly worth consulting before embarking on any mobile activity.


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