I am about to install a GDL 82 in my Waiex. Keep in mind that the supplied Garmin GPS antenna is supposed to be 2 feet from any comm antenna so in my case, that would have required the GPS antenna placement to be unnecessarily far down the turtledeck. Also the antenna is supposed to be level in level flight so the turtledeck may not be ideal.
To avoid these potential problems, as well as not having to incorporate any filters, I am probably going to install a combination COMM/GPS antenna. According to the Garmin manual, this antenna is approved...
https://www.aircraftspruce.com/catalog/ ... kkey=13230 Thus, I'll be diverging from a "cheapest" option a bit but I like things to work the first time and most of the time.
Also note that the Q & A's in the antenna description say that the GDL requires its own proprietary antenna but the Garmin manual specifically approves the above one. *Edit...Aircraft Spruce took my comment and changed the antenna description to confirm that the -200 antenna is approved for the GDL 82.
I'll report back on how it goes!