We plan to take a shot at making a link of 400km or more What we need! is a someone who can tell us, or give as a link to, a calculator that can work with links over 160km. We specifically need to know what elevation we will need at either end in order to make the link work (theoretically). I imagine that at 400km the curvature of the earth is quite a consideration more than anything else.
It is our intention for the vast majority of the link to be over water as well. What should we know that we dont already?
One end is likely to me 2000m above sealevel, and the other end anywhere from 400m ā 800m (is the highest point we have available).
edit I should probably mention we do have a fair amount of experience with shorter links (60 - 100km), and this 400km link is purely a test & a shot at the record
ā¦ damn!!! - there I was thinking the earth was FLAT!!!
Ah wellā¦ Weāll just have to use āhoppersā and repeatersā¦
I donāt want to even let my mind wonder into the relms of āvisitingā - or repairing a BSS 400Km away from me!!
Our futhrest BSS is 140Km away and we have scheduled 3 days a year to āvisitā itā¦ so far so good.
Use long wave radio. Long wave radio travels around the earth. You only need very long antennaās and/or high power.
Or medium radio frequencies (marine) can be used for Ā“bouncingĀ“ around the earth. I canāt remember the exact frequencies but in Shipping and amateur band 400 km is only medium distance.
I can remember some frequencies could only reach certain distances at certain times of the day. This is because the reflective layer around the earth varies in distance to earth surface depending on day or night (sunās energy).
Morse or later TOS (Telex over Radio) traveled around the world, and the data was analogue, although it looked a bit like the digital form we use today. (Morse was long and short beeps, like 0 and 1 in digital. TOS used even bits if I remember well)
So, find a free (amateur) radio wave as carrier for the digital data to be transport. I donĀ“t know how, but can imagine it is possible. I know amateur radio users can transport digital data around the world. Speeds? HavenĀ“t a clue, very low I presume.
May be here the new 801.xxxĀ“nĀ“ technologies could be used to use multi path for different bounces of the radio signals.
This way even ancient radio techniques could transport digital info much faster. IĀ“m not an technician, more a fantast maybe!
What we need! is a someone who can tell us, or give as a link to, a calculator that can work with links over 160km. We specifically need to know what elevation we will need at either end in order to make the link work (theoretically). I imagine that at 400km the curvature of the earth is quite a consideration more than anything else.
