[amsat-bb] HF-HF satellite (horizon?)

Robert Bruninga bruninga at usna.edu
Fri May 27 13:08:10 UTC 2016

> As noted, the entry to Ham radio is not via HF these days, but with no
> HEO sats, one can stretch the footprint pretty well with an HF bird,

Is this true?  On one hand, it makes sense, but on the other hand, the
closer to the horizon the smaller the angle of incidence and the thicker
the ionosphere becomes.  It woiuld seem to me maybe that this would bend
the user's horizon waves downward and therefore miss the satellite.

In other words, I'm thinking that an HF satellite with a footprint that is
2000 miles in diameter would in fact only have an operational range that is
less than that due to bending at those low angles.

On the other hand, some could argue that some ionospheric bending coiuld do
the opposite and enhance somewhat beyond the line of sight horizon... Which
is it?


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