I don't have a lot of experience yet operating MS, but the scattering geometry
is pretty simple- you are scattering from meteor trails that are maybe 100 km
above the ground. If you plug in 100km as antenna height to a radio horizon
(line of sight) calculator, that gives a range of about 1300 km. Twice that is
then the theoretical maximum MS range.
For shorter distances pointing up should theoretically help, assuming your yagi
is fairly high to be free of ground effects.
Astronomers usually use 2 or 3 element yagis pointed straight up for meteor
surveys in order to catch the most possible pings. For example see
http://meteor.uwo.ca/research/radar/cmorII.html
They might be running more than 1.5 KW however :) Has anyone tried such a
simple antenna for shorter distance MS qsos?
Tor
N4OGW
> On Sunday, August 7, 2016 5:13 AM, Les Rayburn <les@highnoonfilm.com> wrote:
> > I’m hoping that someone with more experience with meteor scatter
> > communications
> can answer a question that has been bugging me. Is there any benefit to
> angling
> a Yagi upwards from a horizontal mounting position, say 10-15 degrees for MS
> contacts? I’ve heard some old timers swear that it seems to result in a
> longer
> “ping” or reflection period. Others say it makes little or no difference.
>
> Geometry wasn’t my best subject. :-)
>
> Can anyone speak to this with authority and/or anecdotal evidence? Thanks for
> your expertise in advance.
>
>
>
> 73,
>
> Les Rayburn, N1LF
> 121 Mayfair Park
> Maylene, AL
> EM63nf
>
> Member WTFDA, IRCA, NRC. Former CPC Chairman for NRC & IRCA.
>
> Elad FDM-S2 SDR, AirSpy SDR, Quantum Phaser, Wellbrook ALA1530 Loop,
> Wellbrook
> Flag, Clifton Labs Active Whip.
>
>
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