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Garmin GDL 39 and "antenna diversity"

prkaye

Well Known Member
The ADS-B mandate in Canada in the next couple of years apparently may have an "antenna diversity" requirement. I don't really understand what this requirement will mean, but i gather it would be for sky-facing and ground-facing antennae for the ADS-B system.
Do any you have insight as to whether a Garmin GD-39 portable ADS-B unit would likely meet the future requirements, or be inexpensively augmented to meet the requirement? It looks like a really convenient solution with bluetooth connectivity to a tablet running Garmin Pilot, but I wouldn't to invest in something that won't meet the future regs.
 
Diversity refers to the transmission and reception of data from 2 antennas on a transponder, one on top and one on bottom, the GDL is an ADS-B receiver only.
 
I am willing to bet that "diversity" will cost a lot. It allows tracking of the flight in locations where no ground reception is possible, over the ocean and remote land locations.
 
Do you have a G3X system or GPS like 796, 760, 660, or some other Garmin models? The GDL-39 is used to receive ADS-B IN weather & traffic information to a Garmin screen (like models listed above) when flying in the US only. Doesn't do anything in Canada.

If you are planning for Canada's future ADS-B OUT requirements, best to refer to Nav Canada for requirements. Research mfgrs like Uavionix (TailbeaconX) & a few others for potential options.
Canada, as far as has been stated so far, will not be offering ADS-B IN services to us. There is a private effort somewhere in Ontario that is trying to develop a broadcasting link (weather & traffic) similar to ADS-B IN, but will need to create a ground network acros the whole country to be viable...
 
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Diversity Transponder

The ADS-B mandate in Canada in the next couple of years apparently may have an "antenna diversity" requirement. I don't really understand what this requirement will mean, but i gather it would be for sky-facing and ground-facing antennae for the ADS-B system.
Do any you have insight as to whether a Garmin GD-39 portable ADS-B unit would likely meet the future requirements, or be inexpensively augmented to meet the requirement? It looks like a really convenient solution with bluetooth connectivity to a tablet running Garmin Pilot, but I wouldn't to invest in something that won't meet the future regs.

As mentioned above, the GDL 39 in an ADS-B In receiver, and where available, is capable of receiving ADS-B traffic and weather information, to be displayed on a portable device, or G3X (Touch) System.

The GTX 335D is a Garmin made Diversity transponder, more information on this particular piece of equipment can be found here. Please let us know if you have any additional questions.

Thanks,

Justin
 
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Garmin GTX 335D - List Price $6495 USD
uAvionix TailBeaconX - List Price $2499 USD plus $850 if you don't have a compatible EFIS.
 
Ralph Inkster;1559981 If you are planning for Canada's future [U said:
ADS-B OUT[/U] requirements, best to refer to Nav Canada for requirements.

Please let's get our facts straight. NavCanada does NOT regulate Canadian airspace - that job falls on the shoulders of Transport Canada.

Last year Nav Canada got themselves all would up about announcing an ADSB mandate. They seemed to have forgotten that they only operate the airspace. Eventually our idiot Minister of Transport woke up and told Nav Canada to stand down until Transport Canada had promulgated a regulation mandating ADSB in Canadian airspace.

Now you can bet your bottom dollar that Nav Canada is doing everything in their power to convince Transport Canada to introduce an ADSB mandate which will allow Nav Canada to capitalize on their investment in Aerion. It's up to us to provide Transport Canada with feedback from the other side of the fence.

Diversity has been proven to be significant overkill. Witness the uAvionix tailBeaconX product which is NOT a diversity transponder. Testing done by uAvionix and volunteer Canadian aircraft owners proves quite convincingly that such a product is capable of meeting the operational requirements for compatibility with Aerion satellite-based ADSB.

Bottom line is there is no mandate... yet. The next line up from the bottom is that diversity is not necessarily the only way to get Aerion compatibility. Transport needs to hear us yelling in their ears about this last bit because they love spending other people's money and don't care that they may be passing a regulation which requires us to install a transponder worth half as much as our airplane. They need to hear the other side of the story. Nav Canada is NOT working for you as a GA pilot - they are working for their own bottom line and for the airlines. We need to actively advocate for the needs of General Aviation.
 
Wow! What a passionate response… to what I didn’t say…
I did not say Nav Can regulates Canadian airspace. I did suggest Nav Can might be a good source for what might be ADS-B OUT requirements.
I did try to explain that a GDL39 receiver would be useful only in the US, not in Canada.
I tried to keep my response short as possible & not jump on a soap box and shout my opinions on the injustice of everything.
But I guess no matter what you write, some will read into it what ever they will.
 
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Wow! What a passionate response… to what I didn’t say…
I did not say Nav Can regulates Canadian airspace. I did suggest Nav Can might be a good source for what might be ADS-B OUT requirements.
Your words were: "best to refer to Nav Canada", suggesting NavCanada is the primary source.

I did try to explain that a GDL39 receiver would be useful only in the US, not in Canada.
Which isn't true either. There are a lot of ADS-B and Mode S transponders in Canada, I see them all the time with my Stratux when I fly.
 
"Your words were: "best to refer to Nav Canada", suggesting NavCanada is the primary source."

So? There seems to still be a great amount of confusion amongst some Canadian owners as to the differences & meanings between ADS-B, ADS-B In, ADS-B Out, 1090, 978, UAT, ADS-B-In receivers, ADS-B Out choices, which work where, what might best route for planning be for the POSSIBLE future, mandate or not.
My response to the OP was an attempt to help him understand some of this. Primary (as you put it) source or not, NavCan is a source for information.

I assume you will have the final word. Fine.

As for me, I'm done with this thread.


& I think also, with VAF for a while.
No reflection on the fine format Doug has done in providing VAF to support RVers,
but just done with snark attacks.
 
Some of the early test data released by Aerion showed that the system is capable of receiving ADS-B transmissions from belly-mounted antennas. Nav Canada may have a hard time convincing Transport Canada (or anyone else) that diversity is a hard requirement.

Dave
 
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