August 21st, 2011
The C4 version is actually parallel-connected Doppler ring pairs, while my version is series-connected. The main difference between series-connected and parallel-connected version is the beam angle. The series-connected Doppler rings will have narrower beam angle and theoretically stronger signal.
Both ClearStream C2 and C4 feature reflector mesh (that will make their gain boost quite a bit) and commercial grade packaging. I did not see any guiding ring in the design, which I think it should have. They did not have in-antenna preamplifier, what a pity! The size of these antennas are perfect fit to be mounted in attic and leverage existing house wiring.
To mount these antennas outdoor will require a real pro that helps with proper grounding (so that it won’t be fried under thunderstorm). I personally won’t do that since Californian sun is the most corrosive source for anything that has plastics.