Take the regular ATR formula and divide by close / 100 to normalize. I believe theres a dedicated indicator for it called NATR More on reddit.com

Generally you can't determine the mean from just the range and median, unfortunately. To illustrate: [1, 2, 3, 25, 26, 27, 49] - Range: 1 - 49, Median: 25, Mean: 19 [1, 23, 24, 25, 47, 48, 49] - Range: 1 - 49, Median: 25, Mean: 31 You could possibly approximate if you had more info about the shape of the data, such as the skew. More on reddit.com

I used to get this question from users all the time as a military radio tech. My answer was always "somewhere between ten feet and 10,000 miles, depending on conditions." You could take a bunch of measurements and put all the data into an antenna modeling program, and get a figure that may or may not be in the ballpark, but it's far easier to do trial and error to see what works and what doesn't for your specific situation. A few concepts are mostly universal though; more height above terrain will usually reach out further and receive further, more transmit power will (usually) talk further but won't help with receiving. Buildings, terrain, and vegetation will absorb/reflect RF energy and will reduce range. Lower frequencies punch through vegetation better, higher frequencies (up to UHF range) get through urban environments better. VHF high band is a compromise for operating in varied environments. Higher gain antennas sound good on paper, but are usually only optimal in a few specific circumstances. No such thing as a free lunch with antennas, if you get a benefit in one area, there will be a compromise elsewhere. Clear line of sight will always be the best case scenario. More on reddit.com

Depends on the function More on amp.reddit.com