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I think that I failed my ADS-B test-please assist

John Owen

Well Known Member
Hi,
I checked my ADS-B, a uAvionix replacement for my Navworx EXP on the website for a flight that I took on Sunday on my way back from Petit Jean.

On the test everything looked like no errors except:

NACv missing elements 3.82% MLF 86, NACv Integrity Fail 66.7% with MCF 1719, Category Ave 0.3, and Baro Alt A Fail 6.83% with MCF 5

All of the other checks were 0% fail.

On the uAvionix EchoUAT specification sheet, it says that it is Dual IN/OUT but when I put dual into the option list, it doesn't show uAvionix as an option so I put it in as a UAT which it would take.

I have looked at the FAA help instructions and it says that if several listed parameters are wrong including NACv it means:

Component and/or software compatibility with position source
 Improper system configuration

But it reads to me that all of the parameters would be off which mine are not:

NIC, NACv, NACp, SIL and/or
SDA (100% fail)


Can anyone provide some clarity of what this means? It seems to be working great except for some ghosting on my AFS 5600.

Thanks, so much.
John
RV638DM
 
Hi John,

First, I have the GDL-82 but I had similar errors in the beginning and they turned out to be antenna issues. Location of my GPS antenna was not the best and my transponder antenna didn't utilize the 978 freq. Garmin helped me sort this out.

Were you at a high enough altitude? Terrain? Were you able to see the ground stations? This is available with foreflight if you have it.

Just some suggestions.

Shawn
 
Hi John,

First, I have the GDL-82 but I had similar errors in the beginning and they turned out to be antenna issues. Location of my GPS antenna was not the best and my transponder antenna didn't utilize the 978 freq. Garmin helped me sort this out.

Were you at a high enough altitude? Terrain? Were you able to see the ground stations? This is available with foreflight if you have it.

Just some suggestions.

Shawn

Thanks, Shawn. I will check my antenna. I wasn't sure how most could be OK (darned near perfect) and others not pass.

I was at 5500 ft, about 5000 AGL. But, good thought.

John
 
UAT failed test

John,
Send your FAA report to Uavionx and they will tell you what you need to do.
Mine just needed the transponder sensitivity adjusted. Good to go now after adjustment.
 
my transponder antenna didn't utilize the 978 freq.
The typical spike antennas are cut to cover the 1030-1090 band and are marginal at 978 MHz. Garmin recommends the blade-type broadband antennas but, sadly, the ones they recommend in the GDL-82 installation manual are all expensive. I bought a blade-type Delta-Pop Transponder antenna and it works really well for me. My transponder can be "seen" much further away than my old antenna, and my ADS-B client percentage seems to be higher. I spoke with Don about the Transponder vs. the UAT antennas that he offers and he basically said they're about the same. I bought the Transponder version for $70. http://www.deltapopaviation.com/Transponder_Antenna.html
 
Hello John,

Give me a call at uAvionix 844-827-2372 and select GA support option. I will walk you through the adjustment setting so we can get you a passing PAPR.

Regards,
Kurt
uAvionix Support
 
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