ADS-B Buying Decision

[LDJones]

I really want to buy an ADS-B receiver. I've flown with both the Garmin GDL-39 and the Stratus II. Both have worked great. I'll definitely go with the version with AHRS. The problem is you're making a big-time commitment to the particular app since the two mentioned only support one app each.

I still think ForeFlight has the edge in user-friendliness, but Garmin has been driving hard and is close. The main thing ForeFlight lacks at this point is synthetic vision (SV), which I view as an invaluable backup and the reason to go with an AHRS unit.

Garmin's major shortcoming for me is the lack of IAP overlays. I find them very valuable for situational awareness when approaching my destination. Their interface is also more cumbersome than ForeFlight. But their SV is the best of the bunch. The upside there is it would support my Nexus 7 backup EFB, which is why I subscribe to it as well as ForeFlight.

A dark horse is FlyQ EFB. I actually prefer their UI to Garmin's and it's a close tie to ForeFlight. The plus for them is they are agnostic on ADS-B hardware support. They also have IAP overlays and their SV is only slightly behind Garmin. The downside is the hardware options are more expensive than the other two.

If FireFlight added SV, or Garmin added IAP overlay support, I'd have a much easier decision one way or the other. At around a grand, it's not something you want to buy again in six months.

Anyone else struggling with this decision?

 

[murphey]

It's technology. No matter what you buy, in 6-12 months it will be superceded by domething else.

 

[Clark1961]

With the Stratus II, FF presents AI and HI on a split screen. There is also a stand-alone AI w/heading app. They are still toys of course and I'd have two lose two systems (Aspen and wet pump vacuum fed AI) before I'd think about looking at them.

 

[LDJones]

It's technology. No matter what you buy, in 6-12 months it will be superceded by domething else.

True, but that doesn't necessarily mean you have to replace it if it's providing the functionality you need.

 

[LDJones]

With the Stratus II, FF presents AI and HI on a split screen. There is also a stand-alone AI w/heading app. They are still toys of course and I'd have two lose two systems (Aspen and wet pump vacuum fed AI) before I'd think about looking at them.

I'm hopeful this split-screen feature means ForeFlight is moving that direction. Both Garmin and FlyQ offer split screens. FlyQ gets closest to what I want with SV on the left side of a split horizontal screen, and a nav chart with IAP overlay on the right....a poor man's G500.

 

[Paul Hamilton]

Since I didn't have a smartphone, ipad, or Nexus at the time, one of the big factors was that the Garmin can run on ships power, while the Stratus has a temperature-sensitive internal battery. This would mean having to remove the Stratus after each flight -- too much hassle.

 

[LDJones]

Since I didn't have a smartphone, ipad, or Nexus at the time, one of the big factors was that the Garmin can run on ships power, while the Stratus has a temperature-sensitive internal battery. This would mean having to remove the Stratus after each flight -- too much hassle.

A counterpoint to that is the Garmin uses a proprietary plug (read "expensive") vs. a standard mini USB on the Stratus. For the record, neither have overheated on me, and I took the Stratus to south FL. I also like the substantially longer battery life in the Stratus, a better fit for flight instructing when I move between multiple planes and don't have to mess with chords.

So many factors....

 

[rbridges]

Since I didn't have a smartphone, ipad, or Nexus at the time, one of the big factors was that the Garmin can run on ships power, while the Stratus has a temperature-sensitive internal battery. This would mean having to remove the Stratus after each flight -- too much hassle.

I have a stratus II, and I just lay it on top of my flight bag. It goes home with me afterwards. By the time I pack up my headsets and ipad, I don't even notice having to stick it back in the bag.

 

[frfly172]

Have the stratus II ,does everything I need. Of course avionics change so often who knows for how long. Probably going to install a garmin330 es for adsb out function.

 

[JGoodish]

Since I didn't have a smartphone, ipad, or Nexus at the time, one of the big factors was that the Garmin can run on ships power, while the Stratus has a temperature-sensitive internal battery. This would mean having to remove the Stratus after each flight -- too much hassle.

The Stratus can run on ship's power as well, and the heat issue is easy to avoid in multiple ways, depending on your situation.


JKG

 

[ClimbnSink]

I'm not in the ADS-B game, but if I was I would be waiting until the last minute. See what shows up, see if the rule gets tweaked for better or worse.

 

[Clark1961]

The Stratus can run on ship's power as well, and the heat issue is easy to avoid in multiple ways, depending on your situation

Haven't had trouble with the Stratus II on the glare shield. It just doesn't overheat like the original one did/does. Plenty of battery life too.

 

[LDJones]

I'm not in the ADS-B game, but if I was I would be waiting until the last minute. See what shows up, see if the rule gets tweaked for better or worse.

You mean wait til 2020??! I'll certainly risk $1K now for the benefits of on-board weather NOW! It's just a matter of getting the most bang for the buck with where things are at now.

 

[JGoodish]

You mean wait til 2020??! I'll certainly risk $1K now for the benefits of on-board weather NOW! It's just a matter of getting the most bang for the buck with where things are at now.

I doubt that there will be material changes to FIS-B with respect to the 2020 target. I suspect that Greg was referring to ADS-B Out, and in that case I would more or less agree.


JKG

 

[airdale]

Anyone else struggling with this decision?

Not any more. For my Nexus 7 I switched from Garmin Pilot to iFly and I bought a Skyradar DX, which has the AHRS. Reasons:

• I spent a year waiting for GP/Android to begin catching up with GP/iPad and saw no movement. Their only new features were directed towards selling GDL-39s.
• iFly has a better UI. They are also actively investing in the product and, from the company posts on their forums, seem to be headed in the right direction/adding features that they need to be increasingly competitive. The president and the marketing director are both on the forums and actively engaged with customers. I like that.
• The Skyradar box was on sale/prerelease at $649 with a sticker price of $849. I figured that made it a no-risk buy/easy to flip with no loss if I didn't like it. (Now today I see them advertising it at $722 so maybe that was not such a good deduction.)
• I don't like vendors that try to lock me into their hardware.
• I think the features race for the features that are of use to me is almost over. It's been years since Word or Excel's feature bloat produced anything that I actually use and I expect that situation to apply to EFBs fairly soon. All of them will have everything I need, so the decision goes to the UI and other factors.

Re the comments about waiting and expecting ADS-B to change, I don't expect many changes. FIS-B may get enhanced at the fringes, but ADS-B is already common in the flight levels so it is unlikely that the ADS-B Out specification will change. The only thing that might happen is that TIS-B might start broadcasting all traffic, but this removes a deliberate incentive for people to add ADS-B Out so it seems unlikely.

Long term there are issues, like spoofing being trivially easy, but those will be addressed with an ADS-B Mark II at some point well into the future.

 

[JGoodish]

Re the comments about waiting and expecting ADS-B to change, I don't expect many changes. FIS-B may get enhanced at the fringes, but ADS-B is already common in the flight levels so it is unlikely that the ADS-B Out specification will change. The only thing that might happen is that TIS-B might start broadcasting all traffic, but this removes a deliberate incentive for people to add ADS-B Out so it seems unlikely.

If anything, I suspect that the ADS-B Out hardware landscape is most likely to change. As far as I'm aware, ADS-B Out is not required in any US airspace at this point.

It is my understanding that enhancements to broadcast information are constrained by fairly limited bandwidth, so there may not be much room for enhancement in this area. Regardless, I suspect that any changes in FIS-B or TIS-B would not be hardware dependent.

TIS-B already broadcasts all traffic. The incentive to add ADS-B Out is basically a regulatory one at this point.


JKG

 

[LDJones]

At this point I don't really care about the ADS-B Out...just want the In capability right now.

 

[JGoodish]

At this point I don't really care about the ADS-B Out...just want the In capability right now.

Well, I went with Stratus before the 2 was released, so I can't speak to AHRS. My reasoning was that FF was doing a much better job versus the competition at producing a fairly polished software product, and in my opinion, that remains the case even today. I found many small bugs in GP and WX, and their product support was inferior to FF. I suspect that FF will be adding synthetic vision in the near future.

FlyQ would have to provide some really, really compelling reason(s) for me to consider it. The fact that it is hardware agnostic is nice, but at the end of the day, it's the software and support that get the job done.


JKG

 

[LDJones]

Well, I went with Stratus before the 2 was released, so I can't speak to AHRS. My reasoning was that FF was doing a much better job versus the competition at producing a fairly polished software product, and in my opinion, that remains the case even today. I found many small bugs in GP and WX, and their product support was inferior to FF. I suspect that FF will be adding synthetic vision in the near future.

FlyQ would have to provide some really, really compelling reason(s) for me to consider it. The fact that it is hardware agnostic is nice, but at the end of the day, it's the software and support that get the job done.

I agree on the quality of ForeFlight and their support, although I've had good interactions with both Garmin and FlyQ support, as well. And both of those are nipping at the heels of ForeFlight in terms of features/functions. Competition is good!

 

[AdamZ]

Have you considered Wing X?

 

[JGoodish]

I agree on the quality of ForeFlight and their support, although I've had good interactions with both Garmin and FlyQ support, as well. And both of those are nipping at the heels of ForeFlight in terms of features/functions. Competition is good!

For me it was about overall quality, which is an area where FF excelled. SV isn't worth it to me if the basic functionality is buggy, especially since I'm not going to bet my life on a portable SV solution. My experience evaluating both GP and WingX on two separate occasions did not result in support anywhere close to what FF provides, and I found quite a few bugs which were rather intrusive to the basic functionality of the applications.


JKG

 

[LDJones]

Have you considered Wing X?

I evaluated it early on. It has the functionality, but I didn't care for the UI anywhere near as much as ForeFlight.

 

[frfly172]

Haven't had trouble with the Stratus II on the glare shield. It just doesn't overheat like the original one did/does. Plenty of battery life too.

At sun n fun picked up a window mount for the stratus. Never had a heat problem on the glare shield.with it mounted on the window stays even cooler and easier to access.

 

[Bill Watson]

As an aside can someone talk a bit about how Synthetic Vision plays into this kind of decision?

I'm thinking that the AHRS functionality on a portable provides a backup to panel mounted artificial horizon equipment, perhaps a back up to a backup. And then presenting the horizon on a SV graphic is further optimization of that capability.

At the same time, I'm thinking that no one really uses that capability on a portable, especially if it isn't semi-permanently mounted somewhere up on the panel. Moving plane to plane with say FF probably means using the moving map, weather, traffic, plates, etc but practically speaking, never actually using it's AHRS or SV to actually fly the plane or even for situational awareness, unless it's an AH-related equipment failure emergency, in the soup.

In my flying, I have 3 (experimental GRTs) displays that can display SV at anytime, full screen or split screen. I have a FF iPad mounted in my lap (imagine). But I can't imagine ever using the iPad's AHRS capability (I think it has it). But more to the point, I find zero reasons to ever display SV on any display except the one directly in front of me, unless of course, it failed.

OTOH, I sometimes find myself displaying and using moving maps on 2 screens plus the FF iPad.

I'm not attempting to challenge the thinking here, just understand it.

 

[airdale]

JGoodish, I guess we are going to have to disagree on your points:

If anything, I suspect that the ADS-B Out hardware landscape is most likely to change. As far as I'm aware, ADS-B Out is not required in any US airspace at this point.

I didn't say that ADS-B was legally required, I said that ADS-B Out transmitters are flying in the flight levels. For example, a couple of minutes ago I took my hardware outside and fired it up. SkyRadar immediately reported two targets and, after a little while, reported receiving 137 target updates. Since I am not within range of a 978Mhz TIS-B/FIS-B transmitter, these targets could only have been airliners broadcasting on 1090Mhz, received directly by my SkyRadar box. When flying, I routinely see targets in the flight levels.

It is my understanding that enhancements to broadcast information are constrained by fairly limited bandwidth, so there may not be much room for enhancement in this area. Regardless, I suspect that any changes in FIS-B or TIS-B would not be hardware dependent.

The bandwidth calculations are available in excruciating detail somewhere on the FAA web site. I read the paper a year or two ago. Most of the bandwidth is eaten up by ADS-B Out packets and by traffic/target reports sent by the ground stations. The In and Out are separated by some kind of synchronous system but I don't remember details. FIS-B is not a big deal because it really doesn't have to be timely. The information can be transmitted slowly, over a period of minutes if necessary. I am too lazy to chase down the paper again, but somebody here might be able to jump in with more details.

TIS-B already broadcasts all traffic. The incentive to add ADS-B Out is basically a regulatory one at this point.

What my statement meant was this: The TIS-B broadcasts only include traffic for participating (ADS-B Out) aircraft. This is traffic in a hockey puck 15 miles in diameter and 7,000 feet tall, centered on the participating airplane. If you are a non-participant, like most of us bug-smasher pilots, the traffic you are seeing is somebody else's traffic plus whatever direct 1070Mhz/high flyer signals you are getting.

If you happen to be at the center of the other guy's hockey puck, probably not a good idea, then it is your traffic as well. If you are 3500 feet above him and he is the only participant in the area you may see traffic for 7,000 feet below you but not the guy right behind you descending through your altitude. In the near future there will probably be enough participants flying that in a busy terminal area you will see all traffic because all of the area is in someone's hockey puck, but you will have no way of knowing that. This is the carrot the FAA designed into the system: If you want your traffic, you have to be a participant. What I was suggesting in my post was that the FAA could easily drop this constraint if they chose to do so. I don't think they will.

 

[JGoodish]

JGoodish, I guess we are going to have to disagree on your points:

I didn't say that ADS-B was legally required, I said that ADS-B Out transmitters are flying in the flight levels. For example, a couple of minutes ago I took my hardware outside and fired it up. SkyRadar immediately reported two targets and, after a little while, reported receiving 137 target updates. Since I am not within range of a 978Mhz TIS-B/FIS-B transmitter, these targets could only have been airliners broadcasting on 1090Mhz, received directly by my SkyRadar box. When flying, I routinely see targets in the flight levels.

You made a claim that ADS-B Out is "common" in the flight levels, without quantifying "common," but intimating that it's in use by most of the commercial fleet. Regardless of the numbers, that is in no way an indicator that the standard can't or won't be changed before the mandate(s) become effective. From what I recall, Garmin's GTX330ES required software update(s) after shipment to maintain compliance with the finalized ADS-B Out requirement.

I am not aware of any proposed material changes to the ADS-B In standard which would obsolete hardware. It's always possible and likely that the system will evolve over time, but given how long it's taken to get the current system to a point that isn't yet fully functional, I wouldn't be concerned at all about such an evolution rendering a $1000 portable ADS-B receiver obsolete in a few years.

What my statement meant was this: The TIS-B broadcasts only include traffic for participating (ADS-B Out) aircraft. This is traffic in a hockey puck 15 miles in diameter and 7,000 feet tall, centered on the participating airplane. If you are a non-participant, like most of us bug-smasher pilots, the traffic you are seeing is somebody else's traffic plus whatever direct 1070Mhz/high flyer signals you are getting.

You are correct that TIS-B broadcasts are only triggered by requests, but it is important to note that those broadcast do contain all identified traffic (ADS-B and Mode-C).

I think that it's somewhat conspiratorial to suggest that the request/response nature of TIS-B was done as a carrot for adoption. FIS-B is likely far more valuable to most pilots, and it does not use the request/response model. When all aircraft are equipped with ADS-B Out, theoretically TIS-B won't be required to identify other participating aircraft, as it is not today. I suspect that the reason for the request/response model in TIS-B is for efficiency in the new system that is constrained by decades-old technology.


JKG

 

[flyingcheesehead]

You are correct that TIS-B broadcasts are only triggered by requests, but it is important to note that those broadcast do contain all identified traffic (ADS-B and Mode-C).

TIS-B already broadcasts all traffic. The incentive to add ADS-B Out is basically a regulatory one at this point.

Yes, TIS-B sends both equipped (ADS-B) and non-equipped (Mode C) traffic, but ONLY that which is located within an equipped aircraft's puck. Get close enough to an equipped aircraft, and you'll see him and all of his traffic.

But if you aren't equipped, you won't see other non-equipped traffic. That's why the incentive to add ADS-B is much more than "a regulatory one".

 

[flyingcheesehead]

Since I didn't have a smartphone, ipad, or Nexus at the time, one of the big factors was that the Garmin can run on ships power, while the Stratus has a temperature-sensitive internal battery. This would mean having to remove the Stratus after each flight -- too much hassle.

I believe you were misled - Stratus also runs on ship's power, and the Garmin also has a temperature-sensitive battery (or no battery at all, in which case it's useless as a backup device).

The Stratus has a "Turn on when powered" mode which is quite handy - I never touch my Stratus, it sits on the glareshield and turns on with the master and off 30 seconds after the master gets switched off.

Appareo does say not to let the Stratus battery get too hot or too cold, but that's just as true of Garmin's batteries as it is of the Stratus, your smartphone, your laptop, etc. etc. They're all using Li-Ion batteries that can be damaged by temperature extremes. However, the same is true of aircraft instruments, avionics, and interiors. I leave the Stratus on the glareshield all the time. If it's winter, I have a space heater running in the plane to keep the gyros warm. If it's summer and I'm in my hangar, no problem. If I'm parked outside in the hot sun, the airplane cover goes on. Again, no problem.

 

[Marauder]

At the end of the day Loren, it comes down to which UI you prefer. I don't think any of the industry leaders are going anywhere and what we will see will be more matching features that makes the differentiation more difficult. I took the leap with the GDL-39 primarily because it looks like and acts similarly to my panel mounted GTN I have installed.

As for SV, I don't have it and from the people I know who own it, unless you are flying in the hills, it is more of a novelty for us flat landers. AHRS is a nice to have, but like Clark1961 above, with dual Aspens that are both capable of displaying an AI and the vacuum AI, I would be in serious trouble if I get to the point that I needed it.


Sent from my iPad using Tapatalk

 

[winrose46]

I am still in a quandary with both the skyradar and the dual 170. I put ADS_B out in my bonanza for 6.4 K. The original estimate of 2.4K did not work because my transponder could not be upgraded. The skyradar does not display traffic altitude nor speed on its app or Wing X pro. The Dual 170 displays properly on the Wing X Pro app; however, it does not appear to work with FLYQ EFB. FlyQ EFB does display the weather; however, my only indication that traffic is being received by the app is that my aircraft depiction changes from Blue to Black. Being that I am fanatical about redundancy after my iPad3 overheated and shut down outside of Erie PA in December, I purchased an iPad mini for use as a backup. I am looking for a backup ADS-B device (skyradar does not depict traffic properly in my environment) I may take up iLevil and purchase their SW product (they will provide a $400 credit if I turn in my G =iLevil). I have not verified whether FlyQ EFB will display the traffic better than it does my Dual 170 output. For those on the fence about ADS_B traffic, I could see only 30 % of the traffic during the past 15 hours I have flown with ADS_B out. So much for see and avoid. I am trying to find the funds to purchase ADS_B out for my 172 (~11K ).

 

[John Collins]

I am still in a quandary with both the skyradar and the dual 170. I put ADS_B out in my bonanza for 6.4 K. The original estimate of 2.4K did not work because my transponder could not be upgraded. The skyradar does not display traffic altitude nor speed on its app or Wing X pro. The Dual 170 displays properly on the Wing X Pro app; however, it does not appear to work with FLYQ EFB. FlyQ EFB does display the weather; however, my only indication that traffic is being received by the app is that my aircraft depiction changes from Blue to Black. Being that I am fanatical about redundancy after my iPad3 overheated and shut down outside of Erie PA in December, I purchased an iPad mini for use as a backup. I am looking for a backup ADS-B device (skyradar does not depict traffic properly in my environment) I may take up iLevil and purchase their SW product (they will provide a $400 credit if I turn in my G =iLevil). I have not verified whether FlyQ EFB will display the traffic better than it does my Dual 170 output. For those on the fence about ADS_B traffic, I could see only 30 % of the traffic during the past 15 hours I have flown with ADS_B out. So much for see and avoid. I am trying to find the funds to purchase ADS_B out for my 172 (~11K ).

It is highly likely that your ADS-B Out is not configured properly. It needs to be setup so that the GBT (Ground Based Transceiver - AKA ADS-B Ground Station) knows your ADS-B In capability, otherwise, you get nada from the GBT.

What are you using for your ADS-B Out (both position source and ADS-B Out hardware). For example GNS430W with a GTX330ES.

 

[John Collins]

Yes, TIS-B sends both equipped (ADS-B) and non-equipped (Mode C) traffic, but ONLY that which is located within an equipped aircraft's puck. Get close enough to an equipped aircraft, and you'll see him and all of his traffic.

But if you aren't equipped, you won't see other non-equipped traffic. That's why the incentive to add ADS-B is much more than "a regulatory one".

TISB is only broadcast by the GBT (Ground Based Transceiver - AKA as ADS-B ground station) for non ADS-B aircraft mode C position data to clients. In some cases, if you have a single frequency receiver and you are equipped with ADS-B Out, the GBT will re- broadcast the ADS-B traffic on the other frequency, but this is not TISB, it is ADSR where the R stands for Rebroadcast.

 

[John Collins]

TIS-B already broadcasts all traffic. The incentive to add ADS-B Out is basically a regulatory one at this point.
JKG

This statement is not correct. TISB is only used to broadcast aircraft equipped with mode C transponders, detected by ground radar, and if there is a client requesting the service. TISB is not equivalent to ADS-B as there are several differences, the position is not as accurate, there is no GPS altitude, the aircraft identifier is not broadcast, and the broadcasts are very selective for client aircraft. TISB does not provide ADS-B targets but the ADSR service does rebroadcast these targets under special circumstances based on the capabilities of the client aircraft. For my GDL88 with a dual frequency receiver, the GBT doesn't broadcast ADSR on my behalf since I can receive these targets without the assistance of the GBT.

 

[winrose46]

If the ADS_B Out (GDL-88 with Garmin 430) was not configured properly, Wing X displays would not agree with ATC IFR traffic advisories which they did during my trips to CT and FL this past week. I think it is an issue with FLYQ EFB.

 

[flyingcheesehead]

If the ADS_B Out (GDL-88 with Garmin 430) was not configured properly, Wing X displays would not agree with ATC IFR traffic advisories which they did during my trips to CT and FL this past week. I think it is an issue with FLYQ EFB.

No, even if it's not configured properly the traffic you do see will be in the right place, but it won't broadcast non-ADS-B-equipped aircraft to you.

 

[airdale]

The skyradar does not display traffic altitude nor speed on its app ...

FWIW I have the new SkyRadar DX and the altitude info does display in the iFly app. It's new to me and I don't remember about speed. So I would not say immediately conclude that the SkyRadar box is at fault.

Also (slightly redundant to John Collins' comment) it can be confusing when you are seeing targets. Some targets are displayed because they are participants (ADS-B Out) and the ADS_B In box is receiving their signals directly. Typically I see high-flying airliners this way. Other targets may be displayed because there is a nearby low-altitude participant and you are seeing his traffic. One day I was out underneath a Class B shelf and was seeing lots of traffic; a few minutes later, none. Obviously the participant had landed.

The short way I explain it to people is to say: "If you do not have ADS-B Out, the traffic you are seeing is someone else's traffic." Not 100% accurate I know but it gets the very important point across.

 

[winrose46]

I am seeing non ADS_B out traffic because the ADS_B out traffic appears to have the N number display while the non ADS_B out does not have the N number on the display.

 

[winrose46]

I got a reply from the CTO from skyradar and he indicated "Altitude is displayed right at the target as difference between you and target in hunderds of feet.
Speed corresponds to the length of the arrow symbol.
Also Speed and N-Number (if available) displayed in information window if you pan target to the center of the map" I did not notice any difference in the length of the targets; however, I am going to retry the app. I am concerned that I have to pan to see the display and I did not see the difference altitude readout. Wing X displayed the information properly (in my opinion for both the Dual 170 and the skyradar boxes) where as the skyradar app and the FlyQ EFB had issues in my aircraft. I am leaning towards purchasing the iLevel SW as a skyradar replacement and I have been assured by FlyQ EFB that the iLevel SW does work with their app (eg they indicated that WFI connections do not have the issues that blue tooth have with their app.) I got a 2nd email from skyradar and he said altitude is supressed on the display when the traffic is further away.

 

[Marauder]

It is highly likely that your ADS-B Out is not configured properly. It needs to be setup so that the GBT (Ground Based Transceiver - AKA ADS-B Ground Station) knows your ADS-B In capability, otherwise, you get nada from the GBT.



What are you using for your ADS-B Out (both position source and ADS-B Out hardware). For example GNS430W with a GTX330ES.

Here is an example where I was a parasite on an "out" equipped airplane. I am not "out" equipped. I will typically only get 1090 and the occasional 978 air to air traffic. In these examples, the first photo is what I saw on the map and the second is what was displayed on the Garmin Pilot's traffic page at the same time.

Sent from my iPad using Tapatalk

 

[flyingcheesehead]

I am seeing non ADS_B out traffic because the ADS_B out traffic appears to have the N number display while the non ADS_B out does not have the N number on the display.

That may be traffic that's within someone else's hockey puck, though - Just the presence of non-equipped traffic doesn't guarantee your equipment was properly configured.