GPS Antennas Needed

Hi,

I'm in the process of hooking up all my GPS antennas. I spoke with Garmin today and got the following:

G3X Touch

PFD - install GA-26C
MFD - not needed
GDL39R - not needed
G5 - optional (if any interference issues, install a GA-26C)
GPS-20A - install GA-35

I'm VFR with a tipper canopy. My goal is to have zero of these antennas outside, and not on the glare shield. Will build a shelf firewall forward.

Last question...do I also need to make room for the hockey puck Sirius XM antenna? I have GDU 460s, so that's not built into the device.

Thank you!!!

I have a similar question as your last one. Does it make sense to have a GPS puck on the PFD and an XM puck on the MFD?

Draker said:

Does it make sense to have a GPS puck on the PFD and an XM puck on the MFD?

Click to expand...

It's not enough to have an XM puck, you also need an XM receiver. (Skip to last paragraph).

To get weather graphics available on both screens (I don't know about non-graphical weather information), the weather receiver has to be connected to each screen directly. When I had a GDL39 with only one serial port (not sure about GDL39R connectivity), I got ADS-B weather on both screens by having one screen connected with a serial line and the other connected with bluetooth. When I upgraded to a GDL52, which has two serial ports (and both ADS-B and XM), I hooked up serial connections to both screens and then had two bluetooth connections available for two tablets for when I fly with another pilot.

I have my G3X Touch system set up for two pilots -- engine instruments on the outboard portions of each screen, flight instruments next to that, and the other ("MFD") instrumentation on the inboard halves of each screen. I've found that in the RV-9A, having a full screen MFD on the other side of the cockpit makes it harder to read the center of the screen where most of the useful information is, and that having a full screen MFD rarely displays any significantly useful additional information on the outer portions of the screen.

A minor advantage of XM is better graphics display of radar than ADS-B. Out west, an advantage of XM is coverage down to the ground where ADS-B might not have coverage. That can be an advantage if you're low, the nearest airports are on the other sides of mountains and you need weather information. There are a bunch of other features to consider but a 30 second web search didn't provide any comparison data that I considered up to date.

Just for completeness, I looked on the Garmin website and there are 7" landscape and 10.6" landscape displays that have integrated XM receivers. The trouble with that solution is that (at least) the radar imagery cannot be shared between screens because (I think) CANbus does not have enough bandwidth. You don't have XM receivers in your display screens, so that's a so what.

In any event, you'll have truly amazing capabilities. But there will also be a learning curve to climb, just like with any other glass system...

The GDL 52 ADS-B/XM receiver can provide traffic/weather to both G3X touch screens. The 7" screens do not have internal XM receivers so the 52 is required if you want XM. You will need an XM antenna like the GA 24 MCX.
https://buy.garmin.com/en-US/US/p/529290

I always recommend against installing active GPS antennas FWF, it may work but hot/harsh environments are never good for electronics not to mention the electrical noise from alt/ign etc..

Good points, Ed and Walt. It looks like the GDU 460 (10" landscape) and GDU 450 (7" landscape) displays have versions with XM receivers built in (GDU 465 and GDU 455), but as you point out they cannot share weather data via the CAN bus. Quoting chapter and verse from the installation manual:


The 4x5 displays are $500 more expensive than their 4x0 counterparts, whereas a single GDL 51R runs around $700 (-$200 rebate if you buy a SXM subscription). Looks like the usual cost/complexity trade-off.

Draker said:

Good points, Ed and Walt. It looks like the GDU 460 (10" landscape) and GDU 450 (7" landscape) displays have versions with XM receivers built in (GDU 465 and GDU 455), but as you point out they cannot share weather data via the CAN bus.

Click to expand...

You need a transponder, so get a GTX-45R and get free ADSB WX. No need for an XM enabled PFD/MFD.

On my RV-8 I skipped the cost of an XM-equipped GDU (465)and went with the non-XM GDU (460) portable GDL 52 (non-R unit) with a docking mount and bare wires cable behind the panel and external antennas. I put a similar GDL dock in my other airplanes and now I can swap the 52 around with only one investment in equipment and one Sirius/XM subscription. I can also use it on the glareshield of any aircraft or even a car. The R model is permanent mounted in one airframe which is fine if you only fly that one airplane. I needed the flexibility and battery backup of the non-R model.

Jim

The GDL-52R seems like the path I?m going to take. Originally I was thinking one of the 465 displays but I think the 460 will work better and it allows an incremental spend of $$$. I have a GTX-335 with GPS. Now that I broke down and bought a 430 I?m not sure how many GPS antennas I?m going to have.

Ray. That depends on whether your 430 is a W model or can get position from your GTX 335. I am unclear on that.

One of the nice things about the GDL 39/5X ADS-B "in" units combined with G3X (or a Garmin portable GPS) is that as long as one unit has GPS position it will share that position with the other units. I don't know if the IFR WAAS navigators (GNC, GNX, GTN etc...) will play as well with others.

I just did a Mooney where I put a GDL 52R in the aft fuselage with a GA57X combo GPS/XM antenna on the top of the fuselage. The schematic is attached. The 52R unit is hard wired into an aera 796 on the instrument panel via RS232. The GDL 52R sends GPS position to the 796. The opposite works well too (send GPS location from a G3X or Garmin portable GPS back to a GDL in device). That saves one GPS antenna right there and the GA57X combines the Sirius/XM and GPS into one antenna.

Yeah. Sorry for being unclear. It?s a 430W.

I?m thinking the GDL-52R is connected more like Ed described. Probably use the GA57X antenna.