Garmin GTN Series Interface Issue

Posted Tuesday, August 27 2013 as Q&A

Sandel Tech Note on GTN Software

From Sandel Product Support: Charlie here, I have found a problem with the current software level 5.0 on the Garmin GTN 750/650 series units when interfaced to Sandel displays. The problem is when you have to configure any GAMA output port.

For example:

Port 1 with GAMA Format 3.  When you configure the second ARINC 429 output port to 429 or any other selection, the current software will strip the LONGITUDE label #311 and it will go invalid.

  • What this does when looking at the SN3500 or SN4500 displays, there will be a line thru the GPS1 or GPS2 depending on configuration of the aircraft.  
  • It also causes the flight plan to not be viewable on the EHSI’s.
  • If you are interfaced to the ST3400, it will become invalid.

Garmin is aware of this and should be corrected in the next software release. Until then if you are in the middle of an installation you may have to turn off the output of Channel 2 and move that wiring to the #1 ARINC output of the GTN systems.

This should fix your problems.

If you need any more direction or have questions please visit our product support page or call us at 760.727.4900