Issues with the EchoUAT

maniago
Posts: 68
Joined: Mon Mar 12, 2018 10:34 pm

Issues with the EchoUAT

Post by maniago »

In another forum I'm on, theres a current conversation on the EchoUAT and some issues it has. One of the users (a certified driver) has dove pretty deep into the Echos workings, so with his permission, I'm reposting some of his comments (edited for conciseness) for commentary here on how these things are mitigated with the GRT gear, HXr etc. Not trying to poke fingers, just be an informed consumer. My apologies if I missed some english in the editing.
Thanks for any info.
--------------------

The Echo doesn't do much more than blast out anything it hears.
And it doesn't do it necessarily in a standards compliant way.

1. The software processing of targets is horrible.
To be standards compliant, you should send all traffic targets
in one packet. But, they do absolutely zero filtering on
their traffic, which results in an overwhelming number of
targets. The Echo breaks GDL90 standards by splitting excess targets
into a second partial packet. Oh, and while some EFIS's
can filter targets, some can't (leading to clutter)

2. NavWorX, for example, pre-processed
their target list. You also had the ability to limit the
number of targets that you would send. Maybe 12-18 or so would
be a good practical number (prioritized by distance from you and altitude wrt to you) on an EFIS.

3. Transmitter power is I believe 20W. Ultimately
the wattage should work most of the time, but, you're really
at the bottom bottom end of the power scale with the Echo
compared to other units out there.

4. Signal reception. When doing our work for the filter/processor
box, we logged a lot of GDL90 and watched a lot of planes in the
sky. We compared the echo to the Straux home made system and
found that the Stratux actually had better reception than the
Echo.

5. Blinking targets. One thing that many people have seen
is that the Echo tends to lose targets on the screen.
On second the guy will be there near you, the next it
blinks out and disappears. Coasting helps fix blinking. Uavionix
will say that they don't coast but the EFIS can.

6. The "transponder monitor"
method of Echo CAN work, but, it has limitations.
If you are not under a radar covered area or your transponder
isn't interrogated, it the Echo has nothing to listen to for
baro alt. After a while it'll stop sending baro alt.
That happened to me a lot, and when I'd do an FAA report
on the UAT, it would show lack of baro.

7. Cheap molex connector used. I glued my wires
to the molex now to prevent (them from pushing out), but it's still just not made to a quality (avionics company) standard.

8. Dynon worked for months with Uavionix to get theirs
to perform to their standards before they'd start selling it.
The guts are largely Uavionix based, but improved over the Uavionicx version.
Bobturner
Posts: 444
Joined: Mon Mar 11, 2013 6:34 pm

Re: Issues with the EchoUAT

Post by Bobturner »

There’s a lot of truth in the above post, although, strictly speaking, ADSB-in is not ever required so the poor performance in an EAB is not a legal issue, but rather an operational one. Be nice if it worked better, for sure.
I personally cannot believe the FAA ever approved of transponder ‘sniffers’, whether in the Echo or the NavWorx, for exactly the reasons stated. Nowhere in the FARs can I find, “ Must send out x, y, etc., except when not in radar contact”.
GRT_Jeff
Posts: 802
Joined: Tue Dec 11, 2012 12:11 am

Re: Issues with the EchoUAT

Post by GRT_Jeff »

On the issue of breaking the GDL90 standard and traffic blinking, none or very few of the inexpensive uncertified units are doing any processing. Every inexpensive/uncertified receiver I've seen breaks the standard in some way and mostly just transfers what it receives immediately. When 1090-ES reception was added to the SkyRadar they didn't use GDL90 traffic messages for it and we were forced to implement some traffic processing in the EFIS anyway. The EFIS remembers the targets by address and has a separate timeout for each one. (While in current EFIS models for a long time, this processing was only added to the most recent WS/HS beta update.) We are probably going to add a distance filter setting. Our system does some prioritization by distance so we could put a limit on the number of targets to display. Currently we only have an altitude filter. First the data has to get through the serial connection though and I've heard uAvionix is looking into some filtering on their end.
maniago
Posts: 68
Joined: Mon Mar 12, 2018 10:34 pm

Re: Issues with the EchoUAT

Post by maniago »

Jeff,

Thanks, I figured you guys were all over this and had some processing going on. Does it make more sense to you as a developer to have the Echo and similar boxes provide the firehose so you can implement as you wish, or provide pre-trimmed data? (as a development engr myself, I can see both sides, just curious how you guys view this specific situation).

As for the filtering, is the altitude filter user selectable? I see that the traffic map does have a range setting.....I gather from what youre saying thas just a bulk range setting, not a filtered range setting........
GRT_Jeff
Posts: 802
Joined: Tue Dec 11, 2012 12:11 am

Re: Issues with the EchoUAT

Post by GRT_Jeff »

The problem with the firehose is that it's possible to have more data than you can send through the serial link. We don't analyze the amount of ADS-B traffic coming in while flying so I don't know how often that happens but I've heard the 115200 link can be at full load when you get within range of several towers. Some receivers use higher baud rates but those aren't as common on standard hardware. (For example, on an HX/HXr, only ports 3-8 and the USB ADS-B link can go above 115200.)
GRT_Jeff
Posts: 802
Joined: Tue Dec 11, 2012 12:11 am

Re: Issues with the EchoUAT

Post by GRT_Jeff »

The user altitude filter setting is SET MENU, General Setup, Traffic Altitude Filter.
330drvr
Posts: 69
Joined: Sun Mar 24, 2013 5:30 pm

Re: Issues with the EchoUAT

Post by 330drvr »

I would love to have the range filter. Seeing traffic 60 miles away is just clutter. I have no need to see traffic more than say 10 miles away. I do use and appreciate the altitude filter.
RV-7A
Dual HX, Mini X, dual adaptive AHRS, GRT EIS
rv7charlie
Posts: 28
Joined: Mon Oct 13, 2014 6:28 pm

Re: Issues with the EchoUAT

Post by rv7charlie »

Pardon the thread resurrection, but I'm considering the purchase of a EchoUAT/SafeFly, and I'm hoping for an update on the traffic question in this thread. I see that GRT has some filtering in their EFIS software, but has uAvionix done anything about the 'firehose' nature of their traffic flow?
I'll be using it with a Horizon HX and various android devices.

Thanks,

Charlie
Keith
Posts: 25
Joined: Mon Jan 06, 2020 10:27 pm

Re: Issues with the EchoUAT

Post by Keith »

rv7charlie wrote:Pardon the thread resurrection, but I'm considering the purchase of a EchoUAT/SafeFly, and I'm hoping for an update on the traffic question in this thread. I see that GRT has some filtering in their EFIS software, but has uAvionix done anything about the 'firehose' nature of their traffic flow?
I'll be using it with a Horizon HX and various android devices.

Thanks,

Charlie
Charlie,
I bought an EchoUAT/Safefly combination about a year ago. I have a KT76A transponder. I only used it for "out" as I had an iLEvil AW3 unit for "ADSB IN" which was displayed on my iPad via WingX. I struggled with getting passing ADSB out reports unless I initiated a flight in an "ADSB Rules" airspace and also finished the flight there. I tried changing threshold settings etc and it seemed inconsistent. THEN about a month ago, I installed a GRT Sport EX and am now using that unit for both "out" and "in". When I installed the GRT Sport EX, ALL my problems getting an ADSB out passing report went away. I think that the install also updated the software on the EchoUAT/Safefly unit when I installed it. Bottom, line, all reports I have pulled have been passing even flying outside of "rule airspace". I now see other aircraft that have ADSB out even when I am on the ground. I am not sure what changed but I tried a lot of things to get it right before I installed the Sport EX.

For what it is worth. I would buy that combination again in a heartbeat.
Keith
rv7charlie
Posts: 28
Joined: Mon Oct 13, 2014 6:28 pm

Re: Issues with the EchoUAT

Post by rv7charlie »

Hi Keith,

I appreciate the info. Interesting that installing the EFIS would improve your 'out' performance. Did you switch to using the EFIS as your pressure altitude reporting source when you installed it? I have heard about 'issues' with using some of the older mode C transponders to 'drive' 978MHz ADSB transmitters, but it sounds like your transponder isn't affecting your performance.

Have you played with traffic filtering with the EchoUAT unit? Has uAvionix fixed their 'firehose' issue of sending every target, regardless of altitude/distance?

Thanks,

Charlie
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