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?
Bob, WB4APR
With RS-12, when 10m was open, the satellite could be hard to hear at lower elevations. However, you could sometimes hear it (and use it) while it was on the other side of the planet.
Here's a good write-up from DXCC #1 on RS-12:
http://www.amsat.org/amsat/archive/amsat-bb/200202/msg00707.html
73, Drew KO4MA
-----Original Message----- From: AMSAT-BB [mailto:[email protected]] On Behalf Of Robert Bruninga Sent: Friday, May 27, 2016 9:08 AM To: Amsat BB Subject: Re: [amsat-bb] HF-HF satellite (horizon?)
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?
Bob, WB4APR _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Thanks, Drew. That was exactly the write-up I was remembering!
Greg KO6TH
Andrew Glasbrenner wrote:
With RS-12, when 10m was open, the satellite could be hard to hear at lower elevations. However, you could sometimes hear it (and use it) while it was on the other side of the planet.
Here's a good write-up from DXCC #1 on RS-12:
http://www.amsat.org/amsat/archive/amsat-bb/200202/msg00707.html
73, Drew KO4MA
-----Original Message----- From: AMSAT-BB [mailto:[email protected]] On Behalf Of Robert Bruninga Sent: Friday, May 27, 2016 9:08 AM To: Amsat BB Subject: Re: [amsat-bb] HF-HF satellite (horizon?)
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?
Bob, WB4APR _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
participants (3)
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Andrew Glasbrenner -
Greg D -
Robert Bruninga