ADS-B vs Zaon XRX

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yachtjim

Pre-takeoff checklist
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Jim
I have been using an xrx for a year. It works pretty well at detecting traffic but is not accurate enough for me to have complete confidence in it. I have it connected to a Garmin 796. This week I bought. Gdl39 to use instead. Since I primarily fly in the Northeast I figured ADS-B coverage would be great. As I understand it any plane "in the system" either ifr or using ff should show up of I am in proximity to a transmitter or to another plane with Ads-b out.

On my first flight with it from the DC area to Boston I ran both devices. The Gdl39 missed a lot of obvious targets that I thought it would get. A few jets, and most GA traffic. The Zaon picked most of them up.

I really like how accuretely it displays targets, but if so many are missed I don't find it useful except as a backup to the Zaon. I guess I'll be using both for the foreseeable future. Anybody else using one?
 
That is disappointing to hear. I am putting a 650 in and decided to upgrade the transponder at the same time so I can get traffic. I decided not to get the zaon. Maybe I will need both.
 
Without ADSB Out installed, the GDL39 or any other ADSB receiver only portable based system will only display about 5% or less of the traffic that could be a collision threat. With ADSB Out installed, in the area where there is both ADSB ground station coverage and radar coverage, this will jump to over 95%.
 
But planes near me have ads-b out shouldn't I get updates from them? How close do they need to be? How much is Garmin' cheapest ads-b out solution?
 
The benefit of the Zaon to me is that it works where ADS-B does not. All you need is a transponder that's sending out a "Here I am!" signal, and it can pick it up. It won't send out the "Where are you?" question like an active TCAS will, but it's got some benefit there. I'd expect it to be less accurate than real TCAS simply because of its limitations due to installation.

ADS-B I've found is usually pretty accurate at displaying targets, but I've typically noticed a lag in their position as it gets displayed on my screen. That's to be expected, but when I've flown planes with real TCAS it has been pretty much dead on.
 
yachtjim said:
But planes near me have ads-b out shouldn't I get updates from them? How close do they need to be? How much is Garmin' cheapest ads-b out solution?
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If a target airplane with ADSB Out is near your aircraft, a portable receiver will monitor the target's position by receiving its ADSB position report broadcast via air to air and doesn't require a ground station. So, you will see such a target. About the only aircraft that are currently equipped are the airlines and a few early adopters. You will see plenty of airliners 30,000 feet above you, but they don't represent a collision threat to you. The ones who represent a collision threat to a GA airplane are other GA airplanes, the vast majority which have mode A/C transponders. To detect those aircraft, they have to first be tracked by radar and have the position forwarded to a ground station. The ground station will only broadcast the position data if there is an aircraft that has ADSB Out installed and they are in the proximity of the target. There aren't many of these aircraft out there right now, so you will miss a threat target unless there is a third airplane in the neighborhood that has ADSB to light the target up so to speak. For you to receive the ground broadcast you have to be at a sufficiently high altitude to receive the ground station.

How much it costs to install an ADSB Out unit is very dependent on what you already have installed. It can vary from an extra few thousand to seven thousand or more.
 
Nice explanation, John.

What exactly is picked up for rebroadcast on tis-b?

Does traffic squawking 1200 not receiving radar service (flight following) get picked up and broadcast on tis-b, or only traffic that is assigned a squawk code and provided radar service? Or only IFR traffic?

IF all traffic squawking replies to radar sweeps are picked up and broadcast on tis-b to ads-b out equipped aircraft this would be pretty good coverage for ads-b out equipped ac. Otherwise it would seem that it won't be until approaching 2020 when most ac have ads-b out.
 
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M20Jpilot said:
Nice explanation, John.

What exactly is picked up for rebroadcast on tis-b?

Does traffic squawking 1200 not receiving radar service (flight following) get picked up and broadcast on tis-b, or only traffic that is assigned a squawk code and provided radar service? Or only IFR traffic?

IF all traffic squawking replies to radar sweeps are picked up and broadcast on tis-b to ads-b out equipped aircraft this would be pretty good coverage for ads-b out equipped ac. Otherwise it would seem that it won't be until approaching 2020 when most ac have ads-b out.
Click to expand...

Any target aircraft with a mode A/C or S transponder that is tracked by a ground radar will be broadcast by the GBT as a TISB position when the target is near the client. So regardless of the code that is squawked, it will generate the TISB position report. The only time a TISB report won't be generated is when the aircraft also has ADS-B Out installed.

There are a few qualifications for both the target and client before it can be displayed by a capable client as TISB traffic. They may be obvious, but it is worth stating. The target must be in radar coverage and the client must be line of sight to the GBT. This rules out coverage in the pattern at most airports and in many areas when aircraft are below several thousand feet. The best ADS-B scenario is that the aircraft is a client (has ADS-B Out) and a dual frequency receiver. That way when high enough to be in TISB coverage, all traffic will be able to be displayed and when below TISB coverage, all ADS-B targets will be able to be displayed via air to air reception between the target and the client. The very best of all worlds is an active traffic system with ADS-B as the ADS-B will enhance the position information and provide a greater scope of coverage and below areas of coverage will directly detect transponder traffic.
 
I don't think there is anything wrong with your GDL 39. My hangar neigbor has one connected to the Aera 560 and he had the same experience. We compared it against the Monroy Traffic watch and had similar results. The Traffic Watch showed traffic on the G530W ahead on short final that the GDL39 didn't show. In fact it never showed traffic in the pattern. But the GDL39 showed weather although not as good nor as quick as XM\WX.

José
 
I've had the big Zaon unit (the one that looks like a little Pizza Hut) for a few years and like it a lot. I don't know how much traffic it misses, and know that the azimuth for some of the traffic it reports is not exactly correct. I also know that the distance for the reported traffic appears to be reasonably accurate and that the warning symbols and occasional voice recording are sufficient to get my undivided attention.

The company's repair facility (and maybe more, not sure what all is co-located there) is a few blocks from my hangar, so I recently stopped in to ask if I could borrow one of the new ADS units for eval during the recent NC purple board trip. No loaner units were available, but they were very courteous (as usual) and provided me with an overview of their go-forward philosophy in the traffic awareness arena.
 
John Collins said:
Any target aircraft with a mode A/C or S transponder that is tracked by a ground radar will be broadcast by the GBT as a TISB position when the target is near the client. So regardless of the code that is squawked, it will generate the TISB position report. The only time a TISB report won't be generated is when the aircraft also has ADS-B Out installed.

There are a few qualifications for both the target and client before it can be displayed by a capable client as TISB traffic. They may be obvious, but it is worth stating. The target must be in radar coverage and the client must be line of sight to the GBT. This rules out coverage in the pattern at most airports and in many areas when aircraft are below several thousand feet. The best ADS-B scenario is that the aircraft is a client (has ADS-B Out) and a dual frequency receiver. That way when high enough to be in TISB coverage, all traffic will be able to be displayed and when below TISB coverage, all ADS-B targets will be able to be displayed via air to air reception between the target and the client. The very best of all worlds is an active traffic system with ADS-B as the ADS-B will enhance the position information and provide a greater scope of coverage and below areas of coverage will directly detect transponder traffic.
Click to expand...

John -- I've read the numerous ways to be in compliance with the mandate. Basically, all you need is the ADS-B Out, correct? I think where many of us get confused is the combinations of equipment needed to get both the weather and traffic benefit. There is also some paranoia about installing a mode S transponder (fear that the identification feature of mode S will lead to an easy way to generate user fees).

If you have the setup I have, dual Aspen (both 1000s), a GTN 650 and a mode C transponder, what path would you take? I know there is the Garmin option of the GDL-88 and the new Aspen offerings. Would you move to a mode S to take advantage of the extended squitter?

Sorry for the hijack...
 
Thanks again, John, for the best explanation I've seen yet. Now why don't Garmin or the other portable ADS-B receiver providers explain it that well? Maybe I just missed it in the limited surfing around I did. :)

The take-away for me on ADS-B traffic: not much added value without ADS-B out but very good coverage at enroute GA altitudes here in the NE when ADS-B out equipped. The 5%/95% mentioned in your earlier post. And it will be excellent even in the traffic pattern as we approach 2020 when all AC will be ADS-B out equipped, with WAAS GPS accuracy and in near real time.

So, is it worth springing now for the ADS-B out box in my 430W equipped Mooney? I'm guessing an installed price of about $5K. After all, it is still a "big sky" out there , with flight following, and the old eyeballs. And who knows if I will still be flying in 2020?

Food for thought. How I love understanding new technology!
 
M20Jpilot said:
Thanks again, John, for the best explanation I've seen yet. Now why don't Garmin or the other portable ADS-B receiver providers explain it that well? Maybe I just missed it in the limited surfing around I did. :)

The take-away for me on ADS-B traffic: not much added value without ADS-B out but very good coverage at enroute GA altitudes here in the NE when ADS-B out equipped. The 5%/95% mentioned in your earlier post. And it will be excellent even in the traffic pattern as we approach 2020 when all AC will be ADS-B out equipped, with WAAS GPS accuracy and in near real time.

So, is it worth springing now for the ADS-B out box in my 430W equipped Mooney? I'm guessing an installed price of about $5K. After all, it is still a "big sky" out there , with flight following, and the old eyeballs. And who knows if I will still be flying in 2020?

Food for thought. How I love understanding new technology!
Click to expand...

I currently have a GTX330 Mode S transponder that provides mode S TIS. Since I am based in the Charlotte area, this provides some level of traffic display. The main problem with mode S TIS is that the areas that are covered are lacking and I hear the lady say "Traffic not Available" all too often. I decided not to go the route of upgrading the GTX330 to ES and my airplane is scheduled into the shop to install a GDL88.

We are fortunate at our airport in that we have a GBT on the field, about 200 yards from my hangar. This means I will be able to receive local weather before takeoff. Also, since radar coverage starts about 500 feet AGL, I expect to see traffic in the pattern, but not on final.
 
Marauder said:
John -- I've read the numerous ways to be in compliance with the mandate. Basically, all you need is the ADS-B Out, correct?
Click to expand...

Yes.


I think where many of us get confused is the combinations of equipment needed to get both the weather and traffic benefit. There is also some paranoia about installing a mode S transponder (fear that the identification feature of mode S will lead to an easy way to generate user fees).

If you have the setup I have, dual Aspen (both 1000s), a GTN 650 and a mode C transponder, what path would you take? I know there is the Garmin option of the GDL-88 and the new Aspen offerings. Would you move to a mode S to take advantage of the extended squitter?
Click to expand...

I would not upgrade the Mode C transponder to a mode S transponder with ES unless you have a need to operate above 18000 MSL. I already have a mode S transponder and have no plans to update to ES. The GTN650 has excellent support for ADS-B with the GDL88, better than the support available on my GNS530W, both in terms of traffic and weather products. By keeping your mode C transponder, the GDL88 supports anonymous mode when you squawk 1200. In anonymous mode, a random identifier is used so no one knows who you are and they can't send you a bill. Of course this only works when you are VFR and not receiving ATC services. When you squawk any code other than 1200, a UAT must use the ID that relates to your N number. If you install a mode S transponder, like I have, whether it is ES or not, anonymous mode is not permitted as you would end up with two identifiers, one random and one related to your N number. ATC can't permit you being two targets.

The Aspen unit is priced similar to the Garmin unit, but the Garmin unit can be installed today.
 
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I recently upgraded my transponder to a garmin 327 to eliminate a conflict between my zaon and Collins transponder. I have a 496 that gets a direct feed from the 530 (soon to be 530W) for routing so I leave the zaon to report traffic. I think the zaon is worth every penny spent for the extra traffic avoidance.

Who knows what equipment will be available to us by the time ADS-B is mandatory. I hope I'm still flying by then!

My vote is for the zaon and xm wx.
 
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John Collins said:
Yes.




I would not upgrade the Mode C transponder to a mode S transponder with ES unless you have a need to operate above 18000 MSL. I already have a mode S transponder and have no plans to update to ES. The GTN650 has excellent support for ADS-B with the GDL88, better than the support available on my GNS530W, both in terms of traffic and weather products. By keeping your mode C transponder, the GDL88 supports anonymous mode when you squawk 1200. In anonymous mode, a random identifier is used so no one knows who you are and they can't send you a bill. Of course this only works when you are VFR and not receiving ATC services. When you squawk any code other than 1200, a UAT must use the ID that relates to your N number. If you install a mode S transponder, like I have, whether it is ES or not, anonymous mode is not permitted as you would end up with two identifiers, one random and one related to your N number. ATC can't permit you being two targets.

The Aspen unit is priced similar to the Garmin unit, but the Garmin unit can be installed today.
Click to expand...

Thanks for the advice John! One feature I like on the Aspen offerings is the support it will provide for an iPad device. Supposedly it will allow integration of this technology along with feeding the MFD. I would expect more and more capabilities and options may come forward as time passes. Just don't want to get caught in a last minute effort to comply.
 
I have a Garmin GTS330 with Mode S TIS. Since I use a portable 496, it makes things interesting when the 496 isn't being used but the Bitchin' Betty is on audio. I've also noticed it is easy to spoof TIS doing step turns.
Not an entirely foolproof system but nice to have a little more SA.
 
Marauder said:
Thanks for the advice John! One feature I like on the Aspen offerings is the support it will provide for an iPad device. Supposedly it will allow integration of this technology along with feeding the MFD. I would expect more and more capabilities and options may come forward as time passes. Just don't want to get caught in a last minute effort to comply.
Click to expand...

Good point on the option to provide data to an iPad.

Garmin has been issued a patent on their GDL88 feature to interrogate the "on board transponder" to get the squawk code and ident. The UAT has to remain synced with this information and many of the existing transponders don't have a serial interface to provide this data. Aspen indicated that they were going to listen to the transponder to obtain the same information. Without this feature, installing a UAT will be more expensive anytime that an older transponder is used as it will need to be replaced to one that has a serial interface. On my reading of the patent, Garmin covers the technique that Aspen said they were going to use. It will be interesting to see how this plays out, particularly how Aspen will avoid infringing on the Garmin patent.
 
John Collins said:
Good point on the option to provide data to an iPad.

Garmin has been issued a patent on their GDL88 feature to interrogate the "on board transponder" to get the squawk code and ident. The UAT has to remain synced with this information and many of the existing transponders don't have a serial interface to provide this data. Aspen indicated that they were going to listen to the transponder to obtain the same information. Without this feature, installing a UAT will be more expensive anytime that an older transponder is used as it will need to be replaced to one that has a serial interface. On my reading of the patent, Garmin covers the technique that Aspen said they were going to use. It will be interesting to see how this plays out, particularly how Aspen will avoid infringing on the Garmin patent.
Click to expand...

That's interesting. Everytime I push the Ident button on my KT-76 the Monroy ATD-300 shows the squawk code in addition to the KT-76 altitude. And there is no wires between the two.

José
 
John Collins said:
Good point on the option to provide data to an iPad.

Garmin has been issued a patent on their GDL88 feature to interrogate the "on board transponder" to get the squawk code and ident. The UAT has to remain synced with this information and many of the existing transponders don't have a serial interface to provide this data. Aspen indicated that they were going to listen to the transponder to obtain the same information. Without this feature, installing a UAT will be more expensive anytime that an older transponder is used as it will need to be replaced to one that has a serial interface. On my reading of the patent, Garmin covers the technique that Aspen said they were going to use. It will be interesting to see how this plays out, particularly how Aspen will avoid infringing on the Garmin patent.
Click to expand...

Aspen has been fairly vocal about their desire to work in an open hierarchy avionics environment. Every time the G men put another obstacle in their path (like the cross fill issue on 430/530s using Connected Pilot), I get a customer letter stating what is going on. I can't blame Garmin for defending their turf, but I also as a consumer want a competitive environment that leads to innovation and reasonable (if aviation will ever be) pricing. Wow me with innovation, not play rough in the sandbox.

I would love to upgrade to get the weather and traffic, but until the kids stop fighting, I'm finding myself standing on the sidelines.
 
Piloto said:
That's interesting. Everytime I push the Ident button on my KT-76 the Monroy ATD-300 shows the squawk code in addition to the KT-76 altitude. And there is no wires between the two.

José
Click to expand...

That would not infringe on the Garmin patent. The Garmin patent uses the data to keep the UAT synced with the transponder. You can find the patent on line.
 
John Collins said:
That would not infringe on the Garmin patent. The Garmin patent uses the data to keep the UAT synced with the transponder. You can find the patent on line.
Click to expand...

I was not thinking about infringing but about Garmin patent uniqueness. After all, all transponder portable ramp test equipment use the same technique. Even before Garmin existed. It is like someone patenting the wheel because there is no wheel patent before.

José
 
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Piloto said:
I was not thinking about infringing but about Garmin patent uniqueness. After all, all transponder portable ramp test equipment use the same technique. Even before Garmin existed. It is like someone patenting the wheel because there is no wheel patent before.

José
Click to expand...

So this is your considered opinion after reading the patent and its claims.
 
Not to resurrect a dead thread, but has anyone actually used the new Zaon MX1090?

I see lots of ads for it, but I have yet to find a person who has used it.

Richman
 
Richman67 said:
Not to resurrect a dead thread, but has anyone actually used the new Zaon MX1090?

I see lots of ads for it, but I have yet to find a person who has used it.

Richman
Click to expand...

I was interested until I found there was no weather and for $200 more I could get a box with weather and traffic.
 
Their service center office is a few blocks from my hangar, so I stopped in a couple months ago to inquire about a loaner box for evaluation use on an upcoming trip. They told me they won't include weather in their unit because they are in the traffic avoidance avoidance business and adding WX and other features could create problems with their industry partners.

I can't figure out how they expect to compete with other products that provide much more diverse functionality, but no my problemo.
 
Scrabo said:
I was interested until I found there was no weather and for $200 more I could get a box with weather and traffic.
Click to expand...

I would nominally agree, but...

I have WSI Sat weather already, and I really like the idea of the Zaon XRX + MX1090. You get ADSB and passive PCAS in one data stream.

Now why Stratus and Garmin won't let you do that is annoying. Both boxes have serial ports that could connect to an XRX.

Richman
 
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