Originally Posted by BobTurner
Since com transmissions (unlike VOR) use vertical polarization, you also should have mounted it as high (or low) on the rib as possible; and then bent it (close to the rib) down (or up) as much as possible.
Thanks for the heads-up Bob. I was trying to get the antenna further away from the cockpit due to the EFIS screen radiating interference. From experience with antennas on small metal structures instead of on the ideal flat metal ground plane I have found that the polarisation is not as clear cut as one would think.
Nevertheless not flying yet, so will experiment and see how it works. My thinking was that it could always be used for VOR/LOC later on (currently no nav radios). Valtronics makes a remote mount Nav receiver which could always be installed later and driven from the EFIS.