I am super uneducated on radios. We have a large farm in eastern Tennessee and are in need of radios that will reach well within 100 mile range. If this is not possible, then what would my radio friends suggest?
I am grateful for the feedback.
Brett
WG Farms
100 miles is going to be difficult/impossible unless you have direct line of sight, and even then that is quite a distance. For that kind of range you’re going to have to look at repeater systems.
To answer your question about “which radio”: It’s not a matter of which radio, but how much power. All radios at the same power will transmit the same distance. It is more a matter of power and path obstructions (trees, houses, hills, mountains, etc.).
While I see what you’re suggesting, it is NOT transmit power that makes a difference of huge scale on a wide area system, it’s receiver performance. Pick an antenna, any antenna - there is no point transmitting more power than the antenna can provide to a receiver. Every system has an optimum balance of receiver sensitivity to transmitter power. In a static system, then it’s not too bad to manage, but the practical issue is that if one end moves, we can go from fully quietening signals, as in, no hiss or noise, to zero, in just a few steps. You can up the output power and still be unheard the other end - so it’s always a balance between practical power and pointless power.
With 100 miles as a target - then depending on geography/topography, the range from any location is limited. I’m a Brit so don’t know if your State is flat grassland, or mountainous. Makes a difference. Can I assume it’s pretty flat farmland? To make cellular phones work, they have multiple cells that overlap and calls get passed from cell to cell as signal strength dies off with distance. Large area systems for two way radio work in a similar fashion. Each area has a mast/tower antennas and repeaters. Normally they’d be telephone/internet connected, but I suspect your’s would be in a field or similar? You’d need power from a big sollar-battery system, but also beams or even dishes to connect each site - or a subscription to Mr Musk at each one. If I assume your 100 mile distance is a circle around the central point, then your ‘cells’ could be 25 miles radius, or perhaps 50 miles, if it sits on a single hill above flatland? You can then see how many cells you’d need to fill the 100 mile circle - and that’s quite a few! If it’s radio links to join them this means 2 repeaters at each site, and more to complete some of the links. That’s around 1 to 3 grand per repeater, plus towers, feeder cable, buildings, power systems and antennas. It could be cheaper to buy a few satellite phones, and much, much simpler - plus, not maintenance or staff time to keep it going. There is a system of HF radios that could possibly do the job - I know they still use HF radio in Australia for long distance comms - but it is not reliable, or predictable and does require skill to use? Being a Brit - we consider 100 miles a long way - after all, nobody in England is more than 100 miles from the sea - and we’d still struggle to cover a circle 100 mile across reliably. Here, the licence would be VERY expensive, the costs of radio sites and gear way too much. We luckily have pretty good cell coverage everywhere, but before we did, only BIG companies could afford wide area radio systems - think electricity, water, rail - those kind of users. Our Police force/Fire radios are County wide, and our Counties are rarely more than 60 miles x 60 miles and hideously expensive to run. There just isn’t anything simple and cheap that will do what you want without significant disadvantages. In the US, I doubt it would be better - probably worse if your farm is very rural and lacking towns and cities with cellular infrastructure?