GRT HX Dual 6.5 w/DigiTrack II and Appareo Help

[PittsCondor]

I'm looking for advice from those of you have been there long before me. I recently purchased a used dual screen 6.5 Horizon HX system with dual AHRS (legacy), dual magnettommeters, and raim GPS version 1. In addition I purchased a TruTrak DigiTrackII 2 axis autopilot with 2 servos. Just before finding this equipment I ordered a new Appareo ESG III with WAAS GPS and Status 3 and an ACK Digital Encoder.

I also have the EIS4000 installed with just about all inputs active. Fuel Flow, Fuel Level, Manifold Pressure, EGT, CHT, Carb Temp, OAT, Oil Pressure, Oil Temp

Lastly I have a Garmin 796 gps mounted in the panel. My Comm is a ICOM 200.

I called GRT and ordered all brand new wiring harnesses that would have come with the system when new. Those should be in in a couple of weeks.

This is all new to me so I have more questions than answers. Here are a few questions I am looking for input on:

1).Should I use the EFIS to feed the encoder data to the Appareo or should I install the digital encoder and feed that back to the EFIS.

2) The GRT EFIS is supposed to have a small GPS antenna. I don't have one yet but am wondering if I can share the GPS info from the Apparreo

3) Should I install a new fuse block and isolate all this new equipment from all other electronics.

4) I plan on mounting the AHRS behind the baggage compartment up high. Will probably buy Van's install bracket.

5) Magnetometers in the wing tip.

I would love to hear from anyone out there on what they recommend on this installation and if there is anything else I need or should leave out.

Thanks is advance.

[bullojm1]

Here are my thoughts....

1).Should I use the EFIS to feed the encoder data to the Appareo or should I install the digital encoder and feed that back to the EFIS.

Yes, use the EFIS. It works well.

2) The GRT EFIS is supposed to have a small GPS antenna. I don't have one yet but am wondering if I can share the GPS info from the Apparreo

According to Appareo (https://www.appareo.com/wp-content/u...SG-Updates.pdf) you cannot:

Q: Can I use Stratus ESG?s WAAS GPS signal to feed other avionics such as a navigator or emergency locator?No, the WAAS GPS position is only available to the transponder for ADS-B out purposes, and, if connected, a Stratus portable ADS-B in receiver.

If the GRT unit has a built in GPS, you should certainly use that. Alternatively, the 796 has a GPS output the GRT can consume, buy a Garmin GPS puck (GPS 18X LVC for example) or the GRT SafeFly 2020 GPS.

3) Should I install a new fuse block and isolate all this new equipment from all other electronics.

People have mixed emotions about this. In the old days, avionics were less tolerant to voltage drops due to engaging the starter. New avionics deal with the voltage drops more gracefully, hence you see less of the avionics master switch. With that being said, I am an electrical engineer and have an avionics switch in my RV and would put another one in my next one. A switch and a fuseblock - that's cheap insurance compared to the cost of avionics.

Also, consider putting in a small auxiliary battery. The GRT screens and AHRS have multiple (I believe three?) power inputs. Throw the aux battery on when you start your preflight and your AHRS will be aligned by the time you roll your plane out of the hangar.

4) I plan on mounting the AHRS behind the baggage compartment up high. Will probably buy Van's install bracket.

Why not mount the AHRS low, and your magnetometer up high?

5) Magnetometers in the wing tip.

May work, depends on what sort of lights you have and the interference they may cause.

[h&jeuropa]

Are you aware that you can fit GRT servos (currently on sale) and use the autopilot features of the EFIS and eliminate the TruTrak?

Jim Butcher

[Mike S]

Originally Posted by h&jeuropa

Are you aware that you can fit GRT servos (currently on sale) and use the autopilot features of the EFIS and eliminate the TruTrak?

Jim Butcher

However, the TruTrak does provide basic heading and pitch info internally so if the EFIS goes wacky then you can still fly on the A/P internals.

In fact, the original documentation of the first gen GRT units said something along the lines of " while we could directly control the servos, it is better to use a stand alone A/P controller"

[PittsCondor]

Yes, I did read that. They are about $1,500 for the pair. I'm trying to get this done on a limited budget so was using what I have available. If I was going all new I would definitely go in that direction.

Originally Posted by h&jeuropa

Are you aware that you can fit GRT servos (currently on sale) and use the autopilot features of the EFIS and eliminate the TruTrak?

Jim Butcher

[PittsCondor]

Thanks for your input I really appreciate it.

Originally Posted by bullojm1

Here are my thoughts....


Yes, use the EFIS. It works well.


According to Appareo (https://www.appareo.com/wp-content/u...SG-Updates.pdf) you cannot:

Q: Can I use Stratus ESG?s WAAS GPS signal to feed other avionics such as a navigator or emergency locator?No, the WAAS GPS position is only available to the transponder for ADS-B out purposes, and, if connected, a Stratus portable ADS-B in receiver.

If the GRT unit has a built in GPS, you should certainly use that. Alternatively, the 796 has a GPS output the GRT can consume, buy a Garmin GPS puck (GPS 18X LVC for example) or the GRT SafeFly 2020 GPS.


People have mixed emotions about this. In the old days, avionics were less tolerant to voltage drops due to engaging the starter. New avionics deal with the voltage drops more gracefully, hence you see less of the avionics master switch. With that being said, I am an electrical engineer and have an avionics switch in my RV and would put another one in my next one. A switch and a fuseblock - that's cheap insurance compared to the cost of avionics.

Also, consider putting in a small auxiliary battery. The GRT screens and AHRS have multiple (I believe three?) power inputs. Throw the aux battery on when you start your preflight and your AHRS will be aligned by the time you roll your plane out of the hangar.


Why not mount the AHRS low, and your magnetometer up high?


May work, depends on what sort of lights you have and the interference they may cause.