Antenna Help

[Bluelabel]

What have you guys beed doing for Antenna and GPS placement and different models... I'm leaning towards a G3X/650 set up.... I see a lot of clean RVs out there without a lot of whiskers or even GPS antennae on the back.... Was thinking of going with 2 bent whip coms below....
Above all, function is key. This will be a full IFR/CC platform. So, not sure about in-wing antennas.....
What about GPS? Does the GA-26c work well remotely mounted? Exactly where and how to mount?
What about the GDL-39r for ADS-B? Remote mount work?
How about VOR/GS?
Any input with specifics and pics would be greatly appreciated...

 

[BobTurner]

You'll get different opinions on this, but mine is:

The Archer wingtip antenna works great for Localizer and glide slope, and acceptably well for VOR.

The Archer wingtip com is not as good as the belly whip. But I have one (a home brew clone, actually) for #2 com, and think it's okay for backup use. Range seems to be about 25% less than belly whip. (I get the local ATIS 20 miles out on the whip, 15 miles out on the Archer). Based on others' reports my Archer com seems to work a bit better than most. I did NOT follow the installation directions.

G420 antenna is mounted on top of the tail cone, sort of over the battery. Works fine.

I cannot help you with the other Garmin stuff.

 

[Bill.Peyton]

John,
I have over 200 hours on my build with great results on my chosen placements.

GNS 430 Antenna is centered directly on top of the cabin cover between doors (no additional ground plane)
G3X dual GPS/XMWX is offset 4" and located over the rear passengers head (no additional ground plane)
Comm 2 antenna is on top rear of the baggage bulkhead (no additional ground plane)
Comm 1 (430) antenna is on belly under right rear seat
Xponder blade antenna is under pilots seat
ADS-B blade antenna is 3ft rear of baggage bulkhead right of centerline
NAV 1 and 2 Archer antennas, one in each wing tip for Nav radio
Marker Beacon Archer antenna in left wing tip

Observations: Many times ground can not hear me on belly antenna, but fine on top of fuse antenna. In air both antennas seem equal from a signal strength perspective. Using the Archer antenna in the wing tip will offset your localizer alignment by the ~15ft. I hope I never need that 15 ft. to see the runway I pick up ADS-B weather on the ground by my hanger @ KSUS
GPS/XM/ADS-B/MB all work flawlessly

Hope this helps

 

[9GT]

My set-up:
Two G3X GPS puck antennas on a shelf under the cowling along with an external WAAS GPS antenna for the GDL 39. One G3X shares an antenna.

GDL 39 ADSB external blade antenna from Deltapop on fuselage bottom

One bent whip Deltapop bent whip Comm antenna on fuselage bottom for GTN 650 Comm 1

One Comant fiberglass whip on top of empennage for GTR 225 Comm 2

One SS angled whip antenna for ACK E-04 ELT on empennage

One GTN WAAS GPS antenna on composite cabin top with ground plane

One Deltapop blade transponder antenna on fuselage bottom.

One Comant fiberglass cat wiskers on the top tip of the VS stabilizer for VOR navigation.

I had a Comant MB antenna in the wing tip but pulled it out when I decided to forgo it.

Yeah I know these external antennas add drag and are ugly but there is nothing that annoys me more than poor radio/navigation performance.

 

[aerhed]

The bent whips under rear seat work great for comm. I've had great reception also with a copper strip V/balun for a VOR/GS inside the cabin top. GPS antennas work well in overhead console. Transponder somewhere aft of cowl under tunnel. Can't find anywhere good to hide the ELT.

 

[tfarrell839]

So many antennas ... So little space

Hey John,

Congrats on the new project(s)

I'm sure you know this, but to clarify for others, antennas will operate through the fiberglass with little loss in effectiveness, so look for options under the cabin top for GPS antennas especially. There are pictures kicking around of people putting some of them up under the cowling as well . . . I think it's too warm, but it seems to be working for them. There's even a space on the vertical. Go with dual bent whip for performance. It's nigh on impossible to space the antennas out as recommended by the manufacturers. Just do your best. And if you think the 10 is tough, you should watch us scratch our heads about the Glasair we're working on.
Also, don't forget about the magnetometer. You'll need to dedicate a space for that, reasonably far from the antennas, motors, iron, and moving parts. If you go with a Garmin unit, you'll most likely want the magnetometer in the wingtip. Also, get a good transponder antennae, not because they work that much better, but because they break less frequently, IMHO.

In a standard setup, for functionality, I would expect to see visible from the exterior of the aircraft two comm ant, one transponder, one ads-b and maybe some nav whiskers above or below the tail. Putting your primary wass gps antennae outside is a good practice too. You'll almost never see it anyway.

Well, hey, at least you don't need the DME, Marker Beacon and ADF

 

[Walt]

For what its worth, on my own aircraft a straight comm antenna works better than a bent whip and there's plenty of ground clearance available. VSWR specs are better as well on the straight comm antennas which likely corresponds to the improved performance. Maybe it doesn't look as good but for me looks is always secondary.

 

[Bluelabel]

Hey John,

Congrats on the new project(s)

I'm sure you know this, but to clarify for others, antennas will operate through the fiberglass with little loss in effectiveness, so look for options under the cabin top for GPS antennas especially. There are pictures kicking around of people putting some of them up under the cowling as well . . . I think it's too warm, but it seems to be working for them. There's even a space on the vertical. Go with dual bent whip for performance. It's nigh on impossible to space the antennas out as recommended by the manufacturers. Just do your best. And if you think the 10 is tough, you should watch us scratch our heads about the Glasair we're working on.
Also, don't forget about the magnetometer. You'll need to dedicate a space for that, reasonably far from the antennas, motors, iron, and moving parts. If you go with a Garmin unit, you'll most likely want the magnetometer in the wingtip. Also, get a good transponder antennae, not because they work that much better, but because they break less frequently, IMHO.

In a standard setup, for functionality, I would expect to see visible from the exterior of the aircraft two comm ant, one transponder, one ads-b and maybe some nav whiskers above or below the tail. Putting your primary wass gps antennae outside is a good practice too. You'll almost never see it anyway.

Well, hey, at least you don't need the DME, Marker Beacon and ADF

Tim,
Good to hear from you. Thanks for the good advice. Both from yourself and everyone.
We need to catch up before KOSH again next year. There's some good bourbon waiting to be imbibed.
I may hit you up directly with some other questions as well.
JW.