Correct xpdnr settings

[rtairey]

Have the full SV system for the last several years, including two screens, 261 transponder and also garmin GTN650 hooked up. I just recently helped a friend finish up his installation of the exact same system (except garmin).

Went for a group flight the other day, and a third flier using foreflight and Stratus II told us that my he could see my friends tail number on the screen but not mine, he told me he has never seen my tail number while flying. I am assuming that since we have the same setup, the observation on the fore flight should be the same. Settings are the same, I am wondering if anyone has any potential fixes.

 

[Dynon]

Assuming that your GTN was on when you took this picture - notice that your GPS DATA line says (GPS OFFLINE). This means that the transponder isn't seeing the direct serial data connection from the GTN with the ADS-B+ format data that it needs to see to enable ADS-B Out. So effectively, you're not transmitting your ADS-B Out position, and that's probably why you weren't being seen.

The most likely reasons for this are the direct GPS position wire not being connected between the GTN and the transponder. Or, the relevant GTN serial port may not be set to the ADS-B+ format (you need the latest GTN software for that option to be available). You're also probably getting a yellow "CAUTION" alert under button 8 on the SkyView display that expands to "XPNDR GPS IN OFFLINE" when you pull up the detail by pushing button 8.

 

[rtairey]

Thanks, The reason that the GPS signal appeared offline is that I took the screen shot in the metal hangar, no signal. I am pretty sure that the garmin is not the issue. This was still a problem when the SV GPS was used for the signal prior to the GTN installation.

 

[dynonsupport]

Does the other flyer also have a Canadian tail number? There's a chance Foreflight doesn't like non-N numbers.

You have had your transponder checked by someone with a Mode-S test set to verify it's all working correctly, right? The test sets can see your N-number.

 

[rtairey]

K, thanks again. Yes, both ships are the same, and Canadian. No, I have not had the transponder checked for mode S. I guess I thought that it was plug and play, nothing else to set up or configure. I have always been seen by ATC, guess I am not now sure what exactly they were seeing. Btw, it is my second xpndr, it is a rebuilt under warranty. First one was replaced for intermittency a couple years ago. Not sure if that matters, did I need to do anything else when it was replaced? If there is nothing else that is apparent, I will try to find someone with a set to check the signal type.

 

[dynonsupport]

In the US, you have to have a transponder check when you build the plane, every two years, and when you change the transponder. Maybe the rules are different up there.

Ultimately, we don't have a great answer why it doesn't work. We see tail numbers here all the time from SkyView transponders, and there isn't more for you to do then put in your tail number and your ICAO code.

We'll ask our transponder and Foreflight experts tomorrow and see what they say.

 

[rtairey]

K, thx. Same rules for transponder checks up here, my last one was a year ago, it passed. I put in a message to him and asked him if he checks for the type of signal (C or S). Will advise.

 

[rtairey]

Ok, I confirmed with the shop that did my last xpndr check in July 2014 that mode S was logged. Wondering if there is anything else I can check for.

 

[rtairey]

Bumped this up to see if there are any recommendations. Avionics shop confirmed that mode S was confirmed at bi-annual certification.

 

[dynonsupport]

Russell,
We don't have any good ideas here. There's no way to turn the transmission of your tail number off. We're still thinking about it.