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Alabama Buckeye
05-16-2022, 05:46 AM
What really burns my bacon or chaps my ass are self presuming experts. I'm not one of 'em, jack of all trades master of none, that's me; except weather forecasting. We're pseudo-scientists and most couldn't forecast the onset of gastrointestinal upset after binging at Taco Bell. Did you know you can get a Doctorate in lying to the public? Know one who got his Phd upon writing a thesis, renaming a phenomena already spoken of since Jesus was 23 years of age. And most wouldn't know sleet from Shinola.

But that's not my beef. I'm researching how to calculate distance to horizon. Found a so-called self anointed "science" source or two. One even gave the distance to horizon of 230 miles as viewed from top of Mt. Everest. Who gives a crap! How did they calculate this? Don't look to https://www.livescience.com/32111-how-far-away-is-the-horizon.html for an answer.
Formula! I need a formula to calculate CORRECTLY the distance to horizon and I stumble onto
https://science.howstuffworks.com/question198.htm ...H'/0.5736 Hot damn a formula! A 6' viewer, eyes at 5.5', can see 3 miles to the horizon. Wait a minute even I can see 0.5736 divides into 5.5' more than 3 times; yep sure enuf 9.58 miles, and here I've long thought 7 miles was the answer. Ok! My 59 foot height antenna has a horizon of 102 miles, great! And my quite well performing Inverted Vee at 20' has nearly a 35 mile reach. Took a while and got the SWR down to 1.2:1.

But just to be sure I google around a bit and find http://www.ringbell.co.uk/info/hdist.htm. Simple enough to plug in a number to get distance to horizon. Input: 59' Output: 9.4 miles :mad2: That's a long freaking way from 102 miles. But no formula, thank you so much :frusty: OK! So who is right!

Three sources so far and none of much use, save for the reinforcement that the internet is 66.6% $%#^&$#@

Looked a bit more and another formula arises, https://www.boatsafe.com/calculate-distance-horizon/ [1.17 x sq root of height], but still no agreement between sources. Looking across the ocean to the horizon, as viewed from height of 5.5', the horizon is 9.59, 3, 2.9, or 2.74 miles away. Getting closer to an agreement!

But what's the gawd's honest fact, the formula?

BTW, for those chomping to view 230 miles from Mt. Everest, it's cold at 29,029', wear extra socks. Don't take my word for it, see the link above. But I will tell you the 1.17 x sq root of 29,029 is 199 not 230; and 1.17 x square root of 59 is 8.98 not 9.4. Experts: Bygone drips under pressure! Next "they" are gonna tell me, I should believe Osama bin Biden isn't incoherent bumbling fool.

mjd420nova
06-01-2022, 08:32 PM
Visual observation has many variables that make a real calculation just an estimate due to differing conditions. Line of sight (LOS) is a calculated value under ideal conditions.

Alabama Buckeye
07-28-2022, 05:36 PM
Thanks Left Coast, mjd420nova for your response. LOS from 29,029' or 5'5" at the ocean's shore, the question of a true formula for calculating distance to horizon still evades me.

Funny was a 10 minute evening rant on 27.385 LSB several daze ago. Somebody felt it necessary to overpower, interrupt and drone on repeatedly; it's the "west coast, not the left coast". Personally, it's is a matter of perspective. Looking at a map you couldn't prove it was the west coast; unless the map had a compass rose. The compass rose defines one truth. What is the compass rose, the truth, for calculating distance to horizon; regardless of obstructions.

D=√(29029.0−0.0)⋅(2⋅(r+0.0)+(29029.0−0.0)) D=208.97miles; neither 230 nor 199

Alabama Buckeye
07-28-2022, 06:49 PM
Objective: Defining the local area? What is the horizontal max power reach, at surface, of an antenna with a 1 λ height AGL with a primary signal lobe axis of 10d above horizon. Using, one formula (right or wrong) for a 11M antenna at the 36' AGL has a horizon of 7 miles. At which point the axis of primary lobe is 10d higher(hgt undetermined); as seen from point of origin. How much further to when the maximum power lobe axis reaches its horizon? Of course this still isn't yet the definition of the full "local" area. But close enough for a goobermint heretic.