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G3X - "EXCHANGE"

Also Interested

Mike,

I am also interested in buying a GDU 370. Please PM me if it is still available.

Thanks,
 
G3x questions

As a14 builder I am thinking a g3x with a gtn 750 might be an excellent panel give. The 750 can be used as the mdf. Is this workable? If so is there any reason foe a second g3x touch. If so what
 
Looking for GDU-370

Anyone upgrading to the touch screen and/or replacing their GDU-370. I'm interested in taking it off your hands.
 
If I install a 370 and 375 will there be only one AHRS box? If one fails how does the backup work?

You can install up to 3 ADAHRS with the G3X, if one fails it annunciates the fault and automatically switches over.
 
With only one ADAHRS are failures (of ADAHRS) common,? I've heard of someone with only one ADAHRS, he had a screen failure and the primary flight information switched right over to the second screen.
 
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Hello all,

I've secured some of the Garmin avionics I'm seeking for my project (including 2 x GDU 370), but I'm still looking for the following items and their associated connectors & installation kits:

GTR 20 or GTR 200 Com radio
GDL 39R ADS-B/Weather
GSU 25 ADAHRS
GSA 28 Autopilot servo (have 1, need one more)

I realize the G3X system is still recent and 2nd hand items will be few & far between, but please let me know if you have anything available.

Many thanks.
 
Instead of the GDL 39R, you could find a used GDL 39. Even though it is a portable, it can be installed permanent and hard wired to the EFIS. It takes a different fitting for the ADSB antenna and there is a specific wire harness you use. New, a mount bracket is included, so make sure if you find a used one, it has the bracket. They operate exactly the same.
 
G3X Issues

When I purchased my G3X kit. I spent several hours at the Garmin OSH2019 booth making sure I understood what I needed and "THEY" understood my needs.

I could have gone w GRT, Dynon, etc...but I choose Garmin which I ordered from a Garmin distributor.

my kit consist of
GDU-465 G3X Touch
GMU22 magnetometer
GTP59 Temp Probe
GSU 25 ADAHRS
GAD29 Data Concentrator
GEA 24 EIA w all sensors.
G5 Std By In FLight Display
Two GSA 28 AP Servo (roll and Pitch)
Remote GTR20 Comm
Remote GTX45R Transponder ADS-B in/out
and GPS 175 used for Navigator and WAAS source for ADS-B

All works fine however the transponder is giving me so many troubles and calling Garmin support is been lets say...NOT GOOD!

I have had 4 test flghts. 1st and 3rd flight w Tranponder working and 2nd and 4th w Transponder going into Fail. When in the ground and iiin the System configuration page, Xpnder shows TRANSMIT FAULT We checked antenna, installed a new one just to trouble shoot and problem persisted.

Complete installation ,pins and connections have been looked twice by 3 different people and all 3 have confirmed all is installed correctly.

Yesterday Customer support for the first time suggested I look at the Software version and confirmed I have version 2.12 They suggested I needed version 3.13. When I requested the software, I was told that I had to take my Experimental GTX45R Transponder to a Garmin dealer for the update........NOT GOOD #2 (BS in my book)

Why do i have the Ethernet cable if I'm not allowed to do my own software update like I do in the GPS175, GDU465, etc....? I'm not changing anything...just updating my software! all my changes are done through the G3X anyway!

NOT HAPPY W GARMIN AT THIS POINT. I have to fly w/out reporting Position/Speed, etc.... to the closest Garmin Dealer who is under a Class B airspace...NOT GOOD #3
 
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When I purchased my G3X kit. I spent several hours at the Garmin OSH2019 booth making sure I understood what I needed and "THEY" understood my needs.

I could have gone w GRT, Dynon, etc...but I choose Garmin which I ordered from a Garmin distributor.

my kit consist of
GDU-465 G3X Touch
GMU22 magnetometer
GTP59 Temp Probe
GSU 25 ADAHRS
GAD29 Data Concentrator
GEA 24 EIA w all sensors.
G5 Std By In FLight Display
Two GSA 28 AP Servo (roll and Pitch)
Remote GTR20 Comm
Remote GTX45R Transponder ADS-B in/out
and GPS 175 used for Navigator and WAAS source for ADS-B

All works fine however the transponder is giving me so many troubles and calling Garmin support is been lets say...NOT GOOD!

I have had 4 test flghts. 1st and 3rd flight w Tranponder working and 2nd and 4th w Transponder going into Fail. When in the ground and iiin the System configuration page, Xpnder shows TRANSMIT FAULT We checked antenna, installed a new one just to trouble shoot and problem persisted.

Complete installation ,pins and connections have been looked twice by 3 different people and all 3 have confirmed all is installed correctly.

Yesterday Customer support for the first time suggested I look at the Software version and confirmed I have version 2.12 They suggested I needed version 3.13. When I requested the software, I was told that I had to take my Experimental GTX45R Transponder to a Garmin dealer for the update........NOT GOOD #2 (BS in my book)

Why do i have the Ethernet cable if I'm not allowed to do my own software update like I do in the GPS175, GDU465, etc....? I'm not changing anything...just updating my software! all my changes are done through the G3X anyway!

NOT HAPPY W GARMIN AT THIS POINT. I have to fly w/out reporting Position/Speed, etc.... to the closest Garmin Dealer who is under a Class B airspace...NOT GOOD #3

Your dealer should take care of this easy peasy. Just pop it out and drive it to them if it is close or ship it. Looks like you have some dealers < 100 miles from you. The upgrade takes about 5 minutes to complete and most of that is hooking it up and disconnecting it. Garmin does this for free at Osh each year (except 2020). For whatever reason, they will not allow us to upgrade our own xponders. I am sure it has something to do with the TSO, liability and lawyers or they don't want to lose control of the software it takes to do the update for some reason. Bottom line is the upgrade is super fast and easy so even if you take it to a dealer that you did not purchase the unit from, they should not charge much for the upgrade.

Best case is your firmware rev is the issue and getting it updated solves the problem. Worst case is that the issue remains after.... Hope you have a favorable outcome!
 
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One point of stickiness is upgrading software for certified avionics. Your airplane may be experimental, but there are still requirements that don't care what kind of airplane.
 
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