Experimental Aviation Forum - Recent Threads

Anusual values for TRK and BRG in G3X Touch

8875078 — Sun, 19 Apr 2026 18:50:50 GMT

Hi, my G3X Touch showed, TRK 2937 and BRG 2945.is it possible? Units?0

GSU-25 project similar to GI-260

Ihab Awad — Tue, 08 Jul 2025 17:25:29 GMT

Greetings,

I would be delighted to talk to Garmin folks about the use of the GSU-25 ADAHRS and data displays similar to the GI-260. I have a lot of open ended questions, but these center around a novel system I have built and how it could either use Garmin technology, or be incorporated into Garmin technology.

Ihab Awad

RE: GSU-25 project similar to GI-260

Garmin-NG — Fri, 12 Dec 2025 22:26:27 GMT

Hi Ihab, thanks for reaching out and being patient with us as we upgraded our forums. If you haven't already send us an email at g3xpert@garmin.com with your questions about the GSU-25 ADAHRS and GI-260.

RE: G3X Touch with autopilot

Garmin-NG — Wed, 10 Dec 2025 16:07:46 GMT

Hi Anthony! There currently is no bluetooth adapter or supporting documentation for what you're wanting to do. If you have any follow-up questions you can contact g3xpert@garmin.com as this is the best way to contact the experimental team.

G3X Touch with autopilot

5537436 — Sun, 30 Mar 2025 12:32:40 GMT

Hello,

I have a Garmin G3X Touch. I can easily use the autopilot thanks to the Garmin's built-in navigation.

Now, I'd like to run the autopilot with GPS points sent via RS-232 to the G3X (via a BT adapter).

Do you have the Garmin programming?

Thanks,
Anthony

"NO ALT" and "NO ADSB" Messages in XPDR box top of G3X screen

Pilot Jay — Sun, 27 Jul 2025 18:18:31 GMT

Seeking possible solution to altitude and ADSB out issue on my Garmin set up.

Dual G3X Touch (GDU 460)

GPS175

GA 36

GTX35R

GSU 25

GMU 11

GHA 15

This set up performed beautifully for over two years. During the Condition Inspection this year there were three possible sources for this current error.

1: A local avionics A&P outfit performed the pitot/static test and the transponder inspection for IFR. The "apprentice" did the actual work and he was rather rough in handling the GSU 25 unit. He also left the ESP feature of the G3X system turned on which had the system going crazy trying to correct the perceived pitch angles during the testing.

2: I moved the GA 26X antenna that connects directly to the Primary Flight Display G3X out from inside the avionics bay (under aluminum and not getting a constant satellite connection) out under the cowling onto the same platform as the GA 36 antenna that provides WAAS GPS for the system.

3: The local avionics A&P outfit also installed the GHA 15 unit.

From the very first flight following the Condition Inspection (mid May 2025) through today the XPDR box at the top of the G3X screen (to the right of the COM and standby COM boxes) will flash a yellow "NO ADSB" above the squawked code often and less often (but still often) it will flash a yellow "NO ALT" above the squawked code before returning to the white XPDR. Class C traffic control has not mentioned not having ADSB or Mode C information but I have pulled PAPR reports and they indicate errors in reporting. Exceptions are noted on NIC, NACp and SIL. Missing Elements has red under BAlt, as well.

The avionics A&P is very busy and has asked me to take photos of various screens while flying but no potential solution has been offered. Any suggestions on where I can begin troubleshooting myself? This is an experimental aircraft and I have the repairman certificate.

RE: "NO ALT" and "NO ADSB" Messages in XPDR box top of G3X screen

Garmin-AH — Fri, 21 Nov 2025 15:08:54 GMT

Hi Pilot Jay thanks for reaching out and being patient with us as we upgraded our forums. If you haven't already send us an email at g3xpert@garmin.com with your wiring diagram and our team can help you with this issue!