View Full Version : Gtx 345

06-08-2016, 01:23 PM
Is anyone successfully using one of the new GTX 345 transponders as an ADS-B traffic/weather source with AFS displays (particularly the 4500 series)? I've asked the Garmin folks for an install manual to see if they list what protocols are supported for third-party displays.

Shawn McGinnis
06-13-2016, 10:03 AM
Looking through the maintenance manual references the GDL 90 protocol. I don't know of any current users that can verify the functionality.

http://goo.gl/zxrnFE page 2-10

06-14-2016, 10:17 PM
Thanks, Shawn. Is the GDL 90 protocol expected to work with the AF4500 screens? It's been awhile since I was in the port setup menus.

I was able to get an install manual from Garmin and they list a couple options for data format via RS232 output:
(intended for GNS 430W/530W):
- ADSB TFC (traffic only)
- ADSB TFC WX (traffic + weather)
(intended for G950/G1000):
- GDL 90 (labeled "legacy traffic," appears to be traffic only, no wx)

Other formats are available via RS422 and ARINC. A bit surprised that there aren't more specifics since their promo materials specifically mention compatibility with third-party displays.

Is the Freeflight 978-XVR fully supported in the 4500 screens? I know there are newer/cheaper options from AFS and Dynon but my understanding is that they are not supported without buying new 5000-series screens with the SV-Bus.


07-06-2016, 03:44 PM
In case anyone else is watching this space for additional info; I received today a note from Garmin support confirming that the GDL-90 protocol as it's been used in the past is NOT available from the GTX345.

The GTX 345 does not support the identical protocol the GSL 90 (sic) uses. You are correct that the weather and traffic are coming out different ports when the GTX is set to use our LEGACY format.

To clarify the comment related to different ports: GDL-90 formatted traffic is available via the RS-232 outputs, but GDL-90 weather is not, it only feeds via other port types.

12-06-2017, 08:22 AM
Are there any updates on either Garmin or AFS side on this?
I would love to get a GTX345, but only if it can display on AFS.

Lenny Iszak

Shawn McGinnis
12-06-2017, 10:31 AM
I doubt Garmin will ever open up its protocol for us to use.