After trying some antennas for DVB-T (active and passive ones) with mixed results I tried to build my own collinear antenna.
- 2m Coaxial-cable ~2€
- Electrical conduit ~0,50€
- some cable ties
- duct tape
Information about collinear ADS-B Antenna: http://www.balarad.net/
General information about collinear antennas: http://en.wikipedia.org/wiki/Collinear_antenna_array
Youtube video on build process: https://www.youtube.com/watch?v=TkUYdCPFXXs