ADS-B reception with RTL SDR dongle and home made collinear coax antenna.

I figured out I wanted to try ADS-B reception with my dustcollecting dongle, and how could I know how much fun that was. The range out of the box was pretty impressive (and I will make a comparison chart later), but I wanted to build a better one. The one I decided to build was a collinear coax antenna. I used cheap RG-6U coax cable with eight segments and a 75 ohm resistor on top. Incredibly easy an quick to build and as far as I can see very efficient. I use windows software RTL1090, and save data into a MySQL database via a PHP script on my server.

This is my reception map, I'm very impressed that with an indoor antenna I'm able to reach at least north-west 150 NM  out to sea. Of course the antenna is mounted on the wall in the north-west corner of my house, and I've got very few obstacles in the vicnity in that direction. Aircraft need to be at cruising altitude as well ~30-40000 feet. The map is created by a tool called SBSplotter, see http://sonicgoose.com/superimpose-polar-plot-in-google-earth/ for more information.

Hopefully I will be building a 12 segment antenna to test later, that will be fun.

Here you can see all ADS-B tracks I've collected for about 20 hours today. 

See http://www.balarad.net/ for detailed instructions on how to build the antenna.