I just went through the decision process for a second VHF antenna for my new Garmin GTR20 Com2. Having seen a few examples of off field landings that put the belly on the ground and completely disabled communications because the VHF antennas were on the belly, I thought it would be a good idea to put the second one on top. This might also help with transmit range and reception when attempting to obtain clearances when on the ground at more remote airports.
The only problem is that standard whip antennas intended for top-mounting look BUTT-UGLY no matter where you locate them on top of an RV because the angle conflicts with the RV’s elegant lines. By chance, I mocked up a BENT-WHIP antenna intended for mounting underneath and, lo and behold, it looked GREAT mounted just behind the bulkhead about midway between the luggage compartment and vertical stabilizer.
I bought two beautiful identical bent-tip “red-tip” antennas from Don at DeltaPop aviation, and will mount one on the top and use the other to replace the heavier and less beautiful one already installed on the belly of my 7A. Don told me that he knows of a number of top-mounted bent whips that work great, and his are lightweight and elegantly tapered from base to tip.There may be momentary intereference with my Waas GPS antenna mounted nearby, but only briefly when transmitting if at all. I’ll be using my GTN750 Com 1 for nearly all in-flight communications in any event, and that will be transmitting through the belly-mount antenna. I’m very happy with this solution.- Otis