This is from Tony at FPVLR regarding boosting the DBS Mod Antenna ; "because they (DBS Mod) are linear polarized and they are too close together, so the RC antenna when is amplified it emits a lot of RF and this RF destroys the video reception sensitivity. This does not happen nearly as much with the FPVLR kit because we use LHCP (left hand circular polarized) antennas on one side and RHCP (right hand circular polarized) antennas on the other side. So when you amplify the RC (which is the strongest stock signal) the video receive antenna will have an attenuation of -27dB because it's opposite polarized, so it's 27db more "deaf" to the rf noise coming from amping the rc signal."