I did my remote install of the SkyRadar L today. I fabricated a RG400 SMA male/female extension cable and velcro'd the SkyRadar to the right sidewall under the glareshield. The original SkyRadar antenna was then extended with the cable which I ran up through a slot for one of the windshield braces and zip-tied in place. I've made a pigtail for the 12VDC connector to the SkyRadar that will be permanently attached to the plane's electrical system rather than have to use the 12V accessory plug.
I suspect an antenna expert would think the antenna is in a terrible position, running almost parallel to the windshield brace, but I had seen a picture of a similar installation that worked well. All I can say is that I flight-tested it today and picked up ADS-B data just as quickly as with the antenna and box sitting on the glareshield! I also did some 360's and flew directly away from the closest ADS-B ground transmitter's approximate direction and never saw any loss of signal.
Just to be on the safe side, however, I did orient the hinge in the antenna so that it can be flipped up more vertical in case I ever had weak reception. But, in the "parallel" position to the brace tube, I can't see it from the pilot's seat, so it presents no obstruction to vision. We had a nice line of weather displayed on the 720 today - unfortunately, I forgot my camera! But be assured, it works great!
John
N750A
Antenna "flipped up" more vertical:
SkyRadar under panel:
Antenna in "normal" position almost parallel to brace so it can't be seen by pilot: