|
-
POSTING RULES

-
Donate yearly (please).
-
Advertise in here!
-
Today's Posts
|
Insert Pics
|

07-02-2011, 08:09 PM
|
|
|
|
Join Date: Oct 2005
Posts: 75
|
|
placement of garmin antennas for dual G3X
I'm hoping someone has the G3X and the Garmin antennas for them. I'm installing two G3X's, one has weather and XM. The question is, where to mount the antennas. One is the white rectangle and the other is the white teardrop. I'm building a 9a tip-up. right now I'm thinking, just behind the plex glass over the baggage area. One beside the other. Would really like to know what is working for others. Thanks
Russel Koch
RV9A
|

07-02-2011, 08:25 PM
|
 |
VAF Moderator / Line Boy
|
|
Join Date: Jan 2005
Location: Dayton, NV
Posts: 12,256
|
|
The Garmin folks that I have talked with cautioned against putting the 430W antenna next to ANY other antenna because it could block it's view in that direction near the horizon. I ended up putting the 430W antenna by itself on the turtle deck, and instead of the big dual antenna, I installed two tiny GPS antennas and an even smaller XM antenna on the glare shield (all on our -3 project). That gives a GPS antenna for each G3X display, and a single XM (for the single receiver).
Paul
__________________
Paul F. Dye
Editor at Large - KITPLANES Magazine
RV-8 - N188PD - "Valkyrie"
RV-6 (By Marriage) - N164MS - "Mikey"
RV-3B - N13PL - "Tsamsiyu"
A&P, EAA Tech Counselor/Flight Advisor
Dayton Valley Airpark (A34)
http://Ironflight.com
|

07-02-2011, 08:39 PM
|
|
|
|
Join Date: May 2009
Location: Beaumont, Texas
Posts: 156
|
|
I've pondered this too...
I have the same dual G3X set-up in my 7, but I haven't put the antennas in yet. When I asked Stein's people about this, they told me that all of these antennas would tolerate the heat under the cowling, so I'm kind of leaning toward that. I've seen several others like this and they work well. Well, as long as you put the antenna where it's not "shadowed" by the firewall, another antenna or any other metal obstruction. You can get creative mounting to the engine mount or the firewall and still have the necessary separation.
The same would apply if you're putting it in the baggage area. Seems to me that I saw pics of somebody that did what you're wanting to do. They fabricated a small "shelf" just behind the roll bar on which to mount the antenna. As I recall, they put one antenna on each side of the fore/aft cross member. But you might get some shadowing from the roll bar or the fore/aft member. You'll also have to look at what the allowable antenna cable length is, but I'm guessing that won't be an issue (stress the guessing part).
If you haven't tried already, I believe there are some other threads that you may be able to search through. There are a LOT of opinions on this. 
__________________
David Welsh
Beaumont, TX
RV-7 N413WD
|

07-02-2011, 11:21 PM
|
|
|
|
Join Date: Oct 2005
Posts: 75
|
|
Placed Outside
If the antennas are placed on the top of the fuselage just behind the plexi glass, would that not give me better reception than on the glaresheild under the plexiglass?. But at what cost to speed? We are building an airplane that is fast, flush rivets,etc, and then we stick on external steps, and whip antennas, elt antennas and more.
Thanks
Russel Koch
|

07-03-2011, 07:14 AM
|
 |
VAF Moderator / Line Boy
|
|
Join Date: Jan 2005
Location: Dayton, NV
Posts: 12,256
|
|
Quote:
Originally Posted by rkochcyxh
If the antennas are placed on the top of the fuselage just behind the plexi glass, would that not give me better reception than on the glaresheild under the plexiglass?. But at what cost to speed? We are building an airplane that is fast, flush rivets,etc, and then we stick on external steps, and whip antennas, elt antennas and more.
Thanks
Russel Koch
|
The GNS 430W antenna is shaped the way it is to create a pretty small amount of drag. I changed my 430 to a 430W in the -8 a few weeks ago, and found that the "W" antenna is MUCH more sensitive to losing lock due to shadowing (aerobatic tests) than the old system. If you have spent the money to go with a WAAS GPS, it pays to make sure it has a good view of the sky.
All the little antennas? They seem to do fine inside my office, with NO view of the world (except a little window....).
Paul
__________________
Paul F. Dye
Editor at Large - KITPLANES Magazine
RV-8 - N188PD - "Valkyrie"
RV-6 (By Marriage) - N164MS - "Mikey"
RV-3B - N13PL - "Tsamsiyu"
A&P, EAA Tech Counselor/Flight Advisor
Dayton Valley Airpark (A34)
http://Ironflight.com
|

07-03-2011, 07:27 AM
|
|
|
|
Join Date: Jan 2005
Location: Granbury Texas
Posts: 1,136
|
|
The issue I had with the 430W was that my original location was on top of the glare shield. I later learned that RF from the EFIS system was knocking out the 430 reception. I have learned that the 430W antenna must be at least 18" from anything producing RF. Also another antenna lesson was that the standard monopole transponder antenna will not work withe the GTX330/430W traffic monitoring and requires a CI-105.
Pat
|

07-03-2011, 07:32 AM
|
 |
|
|
Join Date: Jun 2008
Location: Charlottesville, VA
Posts: 801
|
|
My perspective:
I have a G430W, and a G696 w/XM. All 3 antennas (430, 696, XM) are mounted under the cowl and perform extremely well. The G430W has never lost a lock unless I'm doing acro. When it loses a lock during acro it quickly recovers when I return to non acro flying. When I am flying acro I really don't care that the 430 has lost its lock because I know where I am and I am not enroute anywhere. When I am enroute the 430 has always worked as designed. So for me, the 430 losing a lock during acro is a small penalty for the clean installation that is gained by mounting the antennas under the cowl. YMMV.
__________________
Jim Shannon
RV-8 N52VV
Charlottesville, VA
AFS 4500 EFIS & 3400 EFIS/EM
G430W - SL30 - G327 - G696 - G240
TT DigiFlight II VSVG w/pitch autotrim
VP-X Pro
|

07-03-2011, 07:55 AM
|
 |
|
|
Join Date: Feb 2005
Location: Northwestern USA
Posts: 1,209
|
|
For what it's worth, there are different antennas available for the G3X displays (GA26C for GPS and GA26XM for XM) that are smaller and designed to be mounted inside the airplane or under a fiberglass panel:
I wouldn't recommend putting these in the hot engine compartment, but you could put them on the glareshield if you wanted to.
The TSO GPS navigators (430W etc) obviously have to use the big white antennas and nothing else.
More information in this thread: http://www.vansairforce.com/communit...ad.php?t=61173
mcb
__________________
Matt Burch
RV-7 (last 90%)
http://www.rv7blog.com
VAF #836
Any opinions expressed in this message are my own and not those of my employer.
Last edited by mburch : 07-03-2011 at 08:43 AM.
|

11-26-2011, 06:49 PM
|
|
|
|
Join Date: Oct 2006
Location: Southeast
Posts: 569
|
|
other compatible Garmin xm antennae
Will other xm antennae work with the G3X inside the cabin like those from Garmin that aren't specifically listed in the G3X installation manual?
Thanks,
Mike
|

11-26-2011, 07:03 PM
|
 |
|
|
Join Date: Feb 2005
Location: Northwestern USA
Posts: 1,209
|
|
Quote:
Originally Posted by alcladrv
Will other xm antennae work with the G3X inside the cabin like those from Garmin that aren't specifically listed in the G3X installation manual?
|
The GA55, GA57X, and GX26XM will all work as the XM antenna for the GDU 375.
mcb
__________________
Matt Burch
RV-7 (last 90%)
http://www.rv7blog.com
VAF #836
Any opinions expressed in this message are my own and not those of my employer.
|
| Thread Tools |
Search this Thread |
|
|
|
| Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -6. The time now is 06:48 AM.
|