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G3X ADSB Ghosting

CraigC121

Member
I have the legacy G3X with a GDL 39 installed as my ADSB in solution. Using the uAvionix Sky Beacon for OUT. The problem I am having is G3X randomly reports my aircraft as traffic and don't want to get to a point where I assume the audible "Traffic" alert is me. Is this a problem with the installation, settings on either G3X or uAvionix? Is there a way to force the aircrafts ADSB IN not to see its OUT as traffic?
 
Ghosting

Are you sure it's your equipment and not ATC? Twice in the last month I have had "ghosting" and when I questioned ATC they told me they were having "issues" with their equipment producing ghost images. The first time I did a clearing turn to see who was behind me (After asking ATC if ok) they finally told me they were having problems with their equipment.
 
Ghosting

Earlier today we did some testing between my -6 and a friends -7 that are similarly equipped. His does not announce "traffic" every 3-5 min when there is no other traffic in the area. That's what leads me to believe its something with my airplane. I have flown it this way for about a year but I recently started my IFR training and its a real distraction.
 
I have the legacy G3X with a GDL 39 installed as my ADSB in solution. Using the uAvionix Sky Beacon for OUT. The problem I am having is G3X randomly reports my aircraft as traffic and don't want to get to a point where I assume the audible "Traffic" alert is me. Is this a problem with the installation, settings on either G3X or uAvionix? Is there a way to force the aircrafts ADSB IN not to see its OUT as traffic?

Craig,

If you have a Mode C transponder instead of a Mode S transponder, you will need to enter your ICAO address on the G3X PFD ADS-B Data Link Configuration page.

Once you have done this, the system will share your N-Number with the GDL 39 to prevent ownship determination mistakes.

GDU37X ADSB Configuration Page.png

Steve
 
Earlier today we did some testing between my -6 and a friends -7 that are similarly equipped. His does not announce "traffic" every 3-5 min when there is no other traffic in the area. That's what leads me to believe its something with my airplane. I have flown it this way for about a year but I recently started my IFR training and its a real distraction.

Have you ran an ADS-B performance report?
https://adsbperformance.faa.gov/paprrequest.aspx

Wouldn’t hurt to be sure that your configuration is good. If it isn’t, that could certainly cause what you’re seeing. ForeFlight, and probably the G3X uses an algorithm to detect ownship so as to avoid nuisance traffic alerts. But if your configuration isn’t setup properly, it is possible that the algorithm wouldn’t detect the traffic target is you, and therefore give you a traffic alert.
 
Thank you!

LongEZ,
I believe this is what I was looking for. The ID in configuration page did not match the uAvionics IACO. I made the change and will test fly later today. Thank you all for the help.

Craig
 
Immediately before I bought my airplane a few years ago, the owner had a uAvionix EchoUAT installed for ADSB in and out. It was a "problematic" install, done by an A&P, and was complicated by an inadvertent mis-pinning in the main harness (hard to track down). After fixing that, I still had serious trouble with ghosting. My own image would suddenly appear very close to me, sometimes right on top. I'd get altitude data (same) but no ID and no direction vector. The system would announce "traffic". Then, a minute or two later the image would disappear. Several helpful conversations with uAvionix determined that the EchoUAT antenna was mounted too close to the transponder antenna, and the coax run from the transceiver to the antenna was too long. We had to relocate both transceiver and antenna to the left wing.

That mostly fixed the ghosting problem, but not completely. I fly in a rural ADSB fringe area and still get ghosting randomly and rarely. I've been told that both the installation and software configuration are correct, and that in this area of the country it's just the nature of ADSB. When I do get ghosting, it's virtually always in the northern, less-populated part of the state where there are fewer ADSB ground stations and never in the southern part closer to Minneapolis. In those same low-beacon areas, I also usually get PAPR failures, never when closer to KMSP.
 
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pretty sure that ATC blasts ALL traffic in your "cone" and ownship issues (separating your own ship from all of the traffic sent to you) are the responsibility of the receiving equipment. ATC does not and cannot remove your ship's target from the package, as all airplanes in that cone can and do also receive that packet. While ATC could have issues with sending two targets for any given aircraft, the fact that it was only your ship that was ghosted points to an ownship issue in the receiving equipment; Possibly configuration. Also possible that ATC had a problem and was not sending codes for the aircraft and therefore receiving equipment couldn't filter effectively.

Larry
 
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