1. Nth

    Nth Member

    Hello everyone, first post here, hope I do everything correctly. (Moderators, please feel free to edit as needed.)

    Anyway, flat earthers have recently latched onto a microwave transmission achievement by Exalt Wireless as proof that earth is flat. In 2016, the company managed to make a link over 235 kilometers, ranging:

    This was apparently achieved without repeaters, providing a direct connection from point A to point B.

    Source: https://finance.yahoo.com/news/exalt-sets-world-record-microwave-130500366.html

    Now, the flat earth claim stems from a YouTube comment which states as follows:

    Source: https://www.thedailyplane.com/world-record-shows-evidence-for-a-flat-earth/

    The claim by the flat earther is that the transmitter and receiver are both only mounted 50 feet above sea level, despite the fact that I have been unable to verify this number with Exalt's published materials, which leaves the origin of the 50 feet number in question. Indeed, Exalt's own website notes:

    Source: http://www.exaltcom.com/How-Far-Will-It-Go.aspx

    My point in posting this here is to see if anyone can verify the flat earther's claim, or if, to put it politely, he/she is simply blowing smoke and the transmitters and receivers can be verified to have actually been tall towers situated atop mountains, such that curvature is accounted for as described on the Exalt website linked posted above. I figure that the latter option is the correct one, but I want to do my due diligence (besides, with how this claim is spreading, it would probably wind up here anyway).

    Thanks in advance.
    Last edited by a moderator: Feb 25, 2018
  2. deirdre

    deirdre Moderator Staff Member

    based on his graphic and bolded text,

    he seems to be under the impression that 'across water' and "coast of Lebanon" means ONLY across water. But the coast of Lebanon is pretty mountainous.


    and the Company's press release explains (to me) what "over water means" vs. full overland.

    @Nth I'm not seeing anything in English searches, perhaps it would be easier to write the company and ask where their towers are located. Link them to the Flat Earth claims though or they might think you're a terrorist wanting to blow up their tower.
    Last edited: Feb 26, 2018
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  3. TEEJ

    TEEJ Senior Member

    Quite clear that this is only possible with antennas at elevation. Exalt have a line of sight profiler but you have to register to gain access to it.

    See following where you can position the cursors for line of sight options between Cyprus and Lebanon.

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  4. FatEarther

    FatEarther Member

    Isn't there a formula/calculation that can confirm at what height 2 towers need to be in order to see line of sight at 235km apart taking the earths curvature into account?
  5. FatEarther

    FatEarther Member

    Man I'm confused. I was going to ask where does Exalt claim they got 124miles (235km's) because the Yahoo article doesn't give references other than quoting the CEO and then listing the Exalt website at the end. But when I searched for ExploreAir LR 7 on the website I found the press release that is a copy of the Yahoo link word for word (or visa versa): http://www.exaltcom.com/pressRelease.aspx?id=4256&terms=ExploreAir+LR+7.

    But when I read the link in the original post Exalt seem to say the opposite that 124miles is a myth:

    Source: http://www.exaltcom.com/How-Far-Will-It-Go.aspx

    1) am I reading it wrong and they're saying they did it by having 600m towers?


    2) are they saying you would need 600m towers and it's a myth?

    Someone please set me straight.
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  6. FatEarther

    FatEarther Member

    Is this the calculation:

    Source: https://en.wikipedia.org/wiki/Line-of-sight_propagation#Geometric_distance_to_horizon

    Please note the quoted text above doesn't show the formulae as they're pictures on the wiki page, so you may have to click the source link provided to see the them.
  7. Mick West

    Mick West Administrator Staff Member

    Doing simply with geometry is misleading, but.

    Distance to horizon is sqrt(h^2 + 2rh), so for equal height towers

    2*sqrt(h^2 +2rh) = 235, and r=6371

    Gives h of about 1 km.
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  8. Mick West

    Mick West Administrator Staff Member

    No, you want to use the "actual service range", below that.
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  9. FatEarther

    FatEarther Member

    Mick are you able to do the calculation? Even though I understand BODMAS, I'm still too stupid to do the calculation :(
  10. deirdre

    deirdre Moderator Staff Member

    235 km is 146 miles.
    that page is almost 9 years old, at least. so perhaps back then people weren't getting 124 miles. ??
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  11. FatEarther

    FatEarther Member

    Sorry I was switching between both articles and mixed up my numbers.

    Ah. This is why I got confused. There's no date on the 'How far will it go?" article so I didn't realise it was 9 years old. So 9 years ago it was impossible, but now (actually 2016) it was finally achieved?
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  12. Mick West

    Mick West Administrator Staff Member

    It's a bit confusiong as they switch between h in miles and h in feet (or km/m)

    d = sqrt(2*k*R*h) is a valid approximationwith everything in the same units

    d = 1.41*sqrt(h) has d in miles, h in feet
    1.41 is sqrt(2*(4/3)*3959/5280), with the /5280 correcting for the h in feet

    What's the question again :) ?
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  13. Bunkmeister

    Bunkmeister New Member

    Thank you all for taking up this topic. Flat earthers are spreading this idea in various comment threads and social media channels.

    I have asked flat earthers if they can verify the 50 feet claim by anything other than an anonymous YouTube comment, and I get no replies.
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  14. Trailblazer

    Trailblazer Moderator Staff Member

    Playing with the Metabunk curve calculator, you would only need land a fraction over 3000ft (900 metres) at each end to get the line of sight. (Horizon is 72.5 miles away from 3000ft, with refraction.)

    Looking at the Google Maps terrain view, it's possible to find two points both over 900 metres above sea level, separated by 146 miles, one in Cyprus and one in Lebanon. So you wouldn't even need a tower, in theory, just a transmitter on the ground.


    Close-ups of either end:



    I'm not suggesting these are the actual locations, of course, just showing that it is trivially easy to find locations in Cyprus and Lebanon that have a line of sight of 146 miles between them.
    Last edited: Feb 27, 2018
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  15. Trailblazer

    Trailblazer Moderator Staff Member

    Further confirmation that there is a line of sight from Cyprus to Lebanon:

    From: https://travel.stackexchange.com/a/99012

    And here is a map of the "visibility cloak" from that point. Note the red shading on lots of mountains in Lebanon: https://www.heywhatsthat.com/?view=NI7FLWDV


    Simulated panorama: circled peaks are in Lebanon.

    Last edited: Feb 27, 2018
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  16. Nth

    Nth Member

    Apologies for somewhat disappearing from this thread, school's been busy over the past few days.

    Anyhow, thanks to everybody for the responses. I'll probably send off an email to the company regarding how exactly the towers are positioned (sounds like this is effectively a permanent link, rather than some proof of concept thing), re: @deirdre's suggestion.

    Two things I've been looking at in the meantime, though. First, tropospheric scattering, which I've learned used to be quite common practice before the widespread use of satellites: https://en.wikipedia.org/wiki/Tropospheric_scatter

    Relevant information:

    That would be my best guess in the case of the towers indeed being verifiably 50 feet above sea level. However, once again, I haven't found anything to suggest that the 50 foot claim is even true. On that subject, for two, what I have found are a few sites that log photos of radio and TV masts in Cyprus, none of which look to be even close to just 50 feet above sea level. Sorry for the links, I hope this isn't an issue with the no-click policy; the sites aren't letting me open images in a new tab to link directly.



    Point being, it looks like these towers are designed to be as tall as possible, to transmit as far as possible under typical conditions.
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  17. Nth

    Nth Member

    Following up on the last post, I have found some well-documented information on a 193 km microwave link from Honduras to Roatan Island. Describing the set-up:

    Source: http://blog.aviatnetworks.com/from-the-field/the-worlds-longest-all-ip-microwave-link/

    Seems like this was a former longest direct link, perhaps supplanted by Exalt Wireless's new record. The plus side to analyzing this is that we have published information on the elevations at both ends of the link. Using the Metabunk earth curve calculator, with 193 km for the distance and 1600 meters for the height:

    So, even if refraction were totally ignored, this situation still has a line of sight by over 50 meters. Honestly, seeing stuff like this, as well noting repeated references to the curvature of the earth in literature on the subject of long-range transmission, suggests to me that the comment referenced in the OP is leaving some crucial information out. Besides, like @Z.W. Wolf points out, there are many points on Cyprus and Lebanon within the 235 km window with sufficient elevation to peek over the earth's curvature if the 50 foot number is incorrect.
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  18. Nth

    Nth Member

    No problem; was on one of George Hniatuk's videos when someone posted a comment linking to a mirror of the video. Seemed like such an extreme claim that I had to look into it. I'm still doing some research on the subject, but it seems that no one's been able to confirm the 50 foot number. YouTuber Paul on the Plane mirrored the video, but there are a number of people in the comments section (some flat earthers included) who are questioning this claim, and at least one guy is saying that he's found the coordinates of the towers in question on Cyprus's end. I'll reference that if it winds up panning out.

    Adding an additional wrinkle to the plot is this image headlining an article on the record:

    [Broken External Image]:http://www.cloudwedge.com/wp-content/uploads/2016/02/Microwave-Link.jpg

    Source: http://www.cloudwedge.com/exalt-wireless-shatters-world-record-for-microwave-link-distance-235974/

    If those towers pictured above are indeed the ones used for this record, then we can kiss the 50 foot claim goodbye, unless, you know, those are small-scale toy mountains in the background.
    Last edited: Feb 28, 2018
  19. Trailblazer

    Trailblazer Moderator Staff Member

    I'm pretty sure that is just a stock image. From Tineye:

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  20. Priyadi

    Priyadi Member

    I had a 'conversation' with a flat-Earther that has worked with a few long-range wireless installations. Naturally, he claimed the Earth is flat, and his wireless links actually penetrate Earth's curvature if we were to use the spherical Earth model.

    I found the best response to this is to demand the coordinates and the height of the towers. And it would check out every single time.

    Various vendors of long-range Wi-Fi equipment provide link planning tools to automate calculation. They account for distance, surface topology, the width of Fresnel zone, the height of the towers and obviously, the curvature of the earth, in order to determine if a link is viable.

    Some of the planning tools are listed below. Some require free registration (pretend you are interested in their products).
    This hasn't been mentioned before, but line of sight alone is not enough. The link also needs to clear its Fresnel zone as much as possible. It doesn't have to be 100% free from obstruction, but the more of the Fresnel zone is obstructed, the lower the signal quality. Image from Wikipedia:


    This is a hypothetical 238 km wireless link from Lebanon to Northern Cyprus (permalink to Ubiquiti's planning tool). And it would work according to the link planning tool.

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  21. Arthisus1826

    Arthisus1826 New Member

    According to that link about cyprus to Lebanon visibility, there was a picture showing it was visible.

    However, the claim was that you might be able to see it “once in a lifetime.”

    Considering many objects stop microwaves, would that not destroy the signal too then if the atmosphere is too dirty to be able to see there?
  22. Arthisus1826

    Arthisus1826 New Member

    Also in regards to the previous record distance it is stated that there is line of sight by 50 meters.

    If that is the case then would atmospheric refraction often mess up the rays by more than 50 meters?

    Over that massive distance I would assume that there would be a lot of disconnections due to atmospheric refraction if the height is only cleared by 50 meters.
  23. LDavid47

    LDavid47 New Member

    This a great representation of the cherry picking of facts and science that they use. Referencing something as evidence of Flat Earth despite data from the company that discusses the curvature of the earth? The dishonesty and hypocrisy never ceases to amaze me
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  24. Oops, violated the no-click. My bad. First timer. I'm just going to try and articulate a point here based on the information I've found. So Exalt wireless is the maker of the microwave radios, but they are not the operators. It's most likely that they don't even install or set them up, based on these facts; on their website, they explain that several companies distribute their products. Also on their site, as well as pdf downloadable, are instructions on how and under what conditions to install the hardware, and examples of ideal weather conditions along with troubleshooting. Several wireless internet providers advertise microwave connection from Cyprus to Beirut, such as Cyberia, WISE and Sodetel. They never mention Exalt by name. Exalt themselves do not offer any wireless services, as far as I can tell. So to this effect, I find it highly unlikely that "Joe Mama" was able to contact Exalt and verify the heights of the towers in question. I even continued to trace the WISP's back to the satellite base in Cyprus, known as Makarios Teleport. No mention of exalt, no height specs, however there are a couple pictures of said base and even a YouTube video in English, made by Cyta Global (Cyta, aka Cyprus Telecommunications Authority, is the operator of Makarios and the central communications hub that links Beirut to internet and other telecomms via France). Their website shows C-ban microwave satellites at their base that operate in the same frequency ranges as what's claimed by Exalt. Even Cyta does not mention tower heights and will not give their exact coordinates. So my point in all of this is not that "absence of evidence is evidence of absence." My point is that Joe Mama's credibility is extremely flawed due to the fact that he never mentioned any of these sources, never claims to have contacted anyone who would actually know the elevations of these microwave radios, yet makes a very questionable claim using an unreliable source who wouldn't be involved in the installation of the equipment in the first place.
  25. deirdre

    deirdre Moderator Staff Member

    If Exalt is aware of the record-setting.. which it is, since they released the press report. I'm sure they know which service provider towers managed it.

    Joe Mama's credibility is extremely flawed because the earth is not flat, ergo the towers can't be 50' above sea level. and Exalt's own literature shows the curve of the Earth in calculations.
  26. I agree with you, however, Joe Mama's claim is that the tower height and distance is evidence of a flat earth. Therefore I thought it to be more important to address the "evidence" at hand, rather than just stating "the earth is not flat." That wouldn't necessarily debunk the person's claim about the specifics. If there were in fact 50ft towers producing a line-of-sight connection, it would be worth finding out how that's possible, to show exactly why it does not constitute evidence for a flat earth. But my contention is that he's lying about ever having contacted them. I also agree that they most likely know where the radios are mounted, but the context in which it's written, "...what it believes to be a record breaking 235 km..." can be construed to either mean they believe the distance is a record breaker, or that they believe 235km is the distance in question. In the former context, according to Singer Executive Development, they would be wrong. According to Singer's report, Telettra did a longer hop over water in 1979. Quoted from the article (titled, "The World's Longest Microwave Radio Link"), "This record setting link was 360 km long and crossed the Red Sea over a good part of its path connecting Jebel Ebra, Sudan with Jabal Dakka, Saudi Arabia." http://www.singerexecutivedevelopment.com/the-worlds-longest-microwave-radio-link/
    That strengthens the argument that Exalt may in fact be mistaken or misinformed about some or all of their information, and it may be due to the possibility that they were given incomplete or incorrect third-party information. We know the earth is not flat, but that does not prove that 50ft towers cannot somehow produce a line of sight connection across such a distance. Microwave rays are electromagnetic, and can be refracted by the atmosphere. Although I do not believe Mr. Mama, I find it important to debunk (or otherwise confirm, and henceforth find a realistic explanation to,) his claim, thereby eliminating the misconception that it would "prove flat earth."
  27. theHassan

    theHassan New Member

    This is an old topic, but please allow an addition:

    Radio wave refraction in the atmosphere is not the same as optical wave refraction. Radio waves go a little beyond the optical horizon. Practically, as a rule of thumb, microwave engineers calculate the effective radius of the Earth as 4/3 of the physical radius. This shows that even when optical line of sight is nonexistent, radio line of sight can be possible.


    In the good old days this was done by using a special curved lined paper, plotting the prominant land features over the curved lines and drawing the radio propagation path in a straight line. The link below will show such a plot, which I also embedded as a picture.



    Nowadays, with computer simulation, it is possible to plot the land as a real section of the Earth and drawing the propagation path as a refracted, curved line.

    With correct radiometeorological data (historic averages), it is possible to use actual refractive index instead of 4/3. Practically, the engineer calculates with both, and selects the one which provides grater availability (that is, higher towers).
    Last edited: Jun 11, 2019
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