Topband: Fresnel Zone

[Ray Higgins (W2RE)]

Thanks for the valuable information. 

I did receive some personally notes not shared here on Topband, thanks for the help and the kind words. One indvidual specifically asked If I would share my experience in some sort of presentation about building remote stations, he was interested in the logistics from finding land to local zoning and the actual build. I never thought about doing a presentation but it was an intriguing inquiry, I did send him an album in chronological order of pictures and video (drone) two of the many remote stations we have built the past few years. Both albums have the start to finish…actually we are never really finished!. With that said, here is the two albums if others are interested.

W1/Eastport https://goo.gl/photos/hEX1A4UR6wC6Lopp7 <https://goo.gl/photos/hEX1A4UR6wC6Lopp7>  63/ac

W1/Lubec https://photos.app.goo.gl/oFEmGbpA3eWo8D143 <https://photos.app.goo.gl/oFEmGbpA3eWo8D143>  20/ac  

So, building a remote station 500 miles away from my home-base is nothing new to me! While I’m uncertain if my new personal QTH with nearby marsh will have any effect on the low band antennas, I pretty optimistic the station will play regardless. :)

Thanks again,

Ray Higgins
W2RE.com











> On Apr 20, 2019, at 4:16 AM, shristov <shristov at ptt.rs> wrote:
> 
>> donovanf at starpower.net wrote:
> 
>> The classic source for Fresnel zones as they apply to HF site
>> selection is NBS Technical Note 139:
>> https://nvlpubs.nist.gov/nistpubs/Legacy/TN/nbstechnicalnote139.pdf
> 
> 
> This indeed is a classical source, but it should be noted that the derivation
> assumes that the elevation angle actually used for communication
> is equal to the elevation angle of the peak of lowest ground reflection lobe.
> 
> This may or may not be the case.
> 
> In amateur operation, communication is often done using elevation angles
> well below the peak of the lowest lobe, because of inability to erect very high antennas.
> In such cases, the first Fresnel zones extends much further than the
> equation 3.4-4 predicts. Correct formulas may be derived using the same
> procedure, while separating communication angle from lobe peak angle.
> 
> Using vertical antennas additionally complicates matters.
> I am not aware of any work on this topic.
> 
> 
> 73,
> 
> Sinisa  YT1NT, VE3EA
> 
> 
> 
> _________________
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