Topband: Fresnel Zone

[Emir Memic]

Ray, 

If we are talking about horizontal polarized antennas 
You cant be high enough on 80m/160m 
And there is no needs to think a lot about effects of fresnel zone on 160/80

Not even with 300m high tower

Of course if there are no uphills around you .....but so far understand you 
That location is free with slight slope around

In my mind its  important to have flat or homogeny slope in desired direction 
Effect of excellent soil is not so critical for ground reflection if you are using horizontal polarized antennas!

On other side for vertical antennas soil is more important but directly under the antennas and in closed flied!

In simple words if you can have antenna in saltwater or very close to it put it in 

If you are far away from good soil with vertical (even 1 wavelength) you will need standard numbers of radials under the antenna!

Iif you are on flat terrain with excellent soil you will need very large antenna on high tower to outperform 4SQ on 80m !

On 160m is non sense to even try something else than vertical or vertical arrays


73s
Braco
E77DX


--
Emir Memic
EMS SOLUTIONS
Köhlergasse 12/3
1180 Wien
+4369919227041
emir.memic at emssolutions.at

-----Ursprüngliche Nachricht-----
Von: Topband <topband-bounces at contesting.com> Im Auftrag von Ray Higgins
Gesendet: Donnerstag, 18. April 2019 16:49
An: topband at contesting.com
Betreff: Topband: Fresnel Zone

I have two questions about fresnel zone. 

I just purchased 22.5/ac near the ocean near Machiasport, ME. This is in the Northeast corner of Maine about 30 miles south of Eastport and a Lubec. This is going to be my personal Remote Contest station! I plan to be contesting from this new qth starting in 2020 but will be QRV by mid 2019 for testing.
This qth is anywhere between 1-3 miles from the ocean or the bay, it sits on a high plateau 150’ asl thats slopes in all directions to saltwater (peninsula) except N/NW. The property has a saltwater river and marsh that runs the perimeter from south to north favoring the NE direction,  the marsh is only 50-100' wide and 1500-2000’ away from the property. The land has a gradual slope to the marsh. 

My questions:

1.) Is the saltwater river bed/marsh wide enough to be an effective field in the Fresnal Zone?
2.) What is the wavelengths needed to be within the Fresnal zone of a river/marsh compared to an ocean?

In this photo album (last pic) I have outlined the river saltwater marsh and property boundry from a google earth shot. https://photos.app.goo.gl/ui79t2jFo95b29et6

I’m only concerned about 80 and 160m in the Fresnal Zone. 

Any input would be welcomed. 

Thanks,

Ray W2RE
 

Sent from my iPhone
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