GRT Avionics

In my RV7a I have a choice of using, via a switch, my Bendix King Skymap coupled directly to my Trio pro pilot or connecting my GRT GPS to the Trio via ARINC. No matter what settings of the gains I use the performance of the Trio is noticeably worse than directly from the Skymap. Any settings or tips for better stability and response?

Sorry for the late reply. I have an HX-Trio Pro in an RV-10, so my settings are probably different. But the HX works very well controlling the Trio, and gives you true heading control, as well as VOR and ILS tracking if you have a navy radio.
In going between the GPS and HX for autopilot control, are you switching all 3 wires? Two ARINC plus the serial line.

Rmrrick wrote:In my RV7a I have a choice of using, via a switch, my Bendix King Skymap coupled directly to my Trio pro pilot or connecting my GRT GPS to the Trio via ARINC. No matter what settings of the gains I use the performance of the Trio is noticeably worse than directly from the Skymap. Any settings or tips for better stability and response?

I have the same issue, but with a GNS430W as the other source. The Trio works pretty good with the GNS430W, but is all over the place with the GRT HX.

See my previous comment.
You must switch the A-B ARINC wires and the RS232 line between the 430 and the HX - 3 wires total.
You must set all the HX internal autopilot settings (gain, etc) to appropriate values. Try to figure out what's not right and adjust those particular values. As I recall a few needed significant changes from 100%.
Trio firmware must be newer than about Nov 2012.
Mine works great.

Edit. I think the Trio firmware needs to be Nov 2011 or later, not 2012.