added readme and instructions

README.md

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+## DXCC Beaming positioning
+This is a utility to assist ham radio operators in quickly assessing where they are located relative to the main lobe of a remote station, 
+judging from their current QSOs.
+
+## When to use it
+Let's say you are listening to QSO between two stations and one of those is a DX station you are interested in.
+It would be very helpful to quickly check what is your position realtive to where the DX station is pointing their antennas,
+thus maximising your chances to contact them. If you have already listened to the details of their setup (like antenna, power) during the QSO
+you can quickly decide whether it makes sense to call them now or wait until they turn their antennas to your direction.
+
+## How it works
+You run the program with your own DXCC prefix (which is resolved to your country coordinates) and let it running.
+When you hear the 2 stations you type in their prefixes and you get a calculation of how closer/farther you are relative to the 
+other station and how many degress to the right/left.
+
+For example, if you are located in England and you are listening a station from Canada having a QSO with a station from Italy
+you just have to enter their prefixes in the order "DX TARGET" , where DX is the station of interest (in this case the Canadian station)
+and TARGET is the station of reference (in this case the Italian station).
+in this case we enter "VE I" and we get this result:
+
+```
+Canada -> Italy
+target vs my loc : Beaming diff -4.72 distance diff -1456.94 Km
+DX -> target : Beaming 55.82 distance 6940.97 Km
+DX -> my loc : Beaming 51.10 distance 5484.04 Km
+```
+
+which shows that the DX station (the Canadian station) "sees us" 4.72 to the left and 1456.94 Km closer than the other station.
+Practically we are in the same direction but much closer. 
+
+As another example, while still located in England, a station from Sweden is having a QSO with a station from Greece and we are interested 
+in the station from Sweden. We enter "sm sv" and we get
+
+```
+Sweden -> Greece
+target vs my loc : Beaming diff +68.01 distance diff -1088.88 Km
+DX -> target : Beaming 165.00 distance 2432.35 Km
+DX -> my loc : Beaming 233.00 distance 1343.47 Km
+```
+
+This shows that although we are 1088.88 Km closer than the Greek station we are 68.01 degress to their right, which is quite off the main direction.
+If the station is using a highly directive antenna, we probably are off into their null.
+
+## How to run it
+
+Download the pre-build `jar` from the releases, make sure you have Java 1.8 or later installed and run it on a terminal like this:
+```
+java -jar dxccbeampos-1.0.jar MY_PREFIX
+```
+
+replacing MY_PREFIX with your callsign prefix
+e.g running it for an English prefix, that would be
+
+```
+java -jar dxccbeampos-1.0.jar G
+```
+
+or 
+
+```
+java -jar dxccbeampos-1.0.jar 2E
+```
+