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Garmin GPS 175 and GNX 375 Install

Pdtofly

Well Known Member
Patron
Hello Everyone, who is thinking about installing one of the above units, or the GNC 355, here is what I have learned installing the above units over the last few days.

Settings in the Garmin are,

ARINC
RX EFIS/ADC, HIGH
TX GAMA Format 3, HIGH

RS232
Aviation Output 1. Note: On the 375, the only RS 232 ports with Aviation Output 1 are 1 & 2. On the 175, all three ports have Aviation Output 1.

On the 175 install, we connected it to a SkyView Classic Touch using the ARINC 429 module, but it would work the same way on the HDX screens.

On the 375 install, we connected it to a Dynon D-100 without using the HS34 module, but he only has lateral tracking only using his autopilot until he upgrades to the SkyView HDX next year. We used Serial Port 1 set to Aviation 1 for Autopilot commands and Serial Port 5 RX set to Alt Frmt 1 100FT for his pressure altitude from the D-100. Set the RS232 output from the D-100 to Format 4.

Brian
 
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Do you happen to have a link to the Installation manual for the 375?

Thanks!

Call Garmin Experimental support...they will email you one. Thats what I had to do when I installed my GPS175. They don't publish these install manuals.
 
HS34

For those in this loop I am trying to figure out the various connections for the 375 to the D-100 and Gemini autopilot using the HS34 and have a few questions:
1. Does the D-100/HS34 talk back to the 375 on the 429 Tx connection or is it just Rx receive (I understand that you need the RS232 for the altitude encoder from the D-100 for the transponder section)
2. Is the HS34 429 Tx a passthrough of the 429 Rx on each respective channel? I.e can I daisy chain the 375 429 Rx connection on the HS 34 on to the Gemini Autopilot. Does the A/P need to talk back to the 375? (It does not currently to the 796)
3. I assume the RS232 to the SL30 stays the same so I can sill select the Nav sources via the HS 34
4. I am assuming I can use my current GTX 327 transponder antenna, can I also reuse the existing GDL 82 GPS puck for the 375 GPS functions?

Obviously trying to figure out if this is a fairly straightforward upgrade.
Figs
 
Any chance I could get a copy of an install manual for the GPS-175? On an eternal hold with Garmin Support, no response over email.
 
That's interesting as I've connected a Garmin 175 to an MGL Explorer iefis using Port 1 rx EFIS/ADC, LOW and Tx Port 1 GAMA format 1, LOW, COMMON SDI.
The 175 sends the route to the MGL efis but something is not right because the mgl internal autopilot keeps dropping the left wing and then quickly rolls to the right when tracking the route. At the same time as doing this the 175 aircraft symbol twitches or does not follow the track - with the mgl disconnected it looks fine so I assume the data from the mgl to the Garmin is incorrect.
If anyone has any good ideas I'd love to hear them
 
That's interesting as I've connected a Garmin 175 to an MGL Explorer iefis using Port 1 rx EFIS/ADC, LOW and Tx Port 1 GAMA format 1, LOW, COMMON SDI.
The 175 sends the route to the MGL efis but something is not right because the mgl internal autopilot keeps dropping the left wing and then quickly rolls to the right when tracking the route. At the same time as doing this the 175 aircraft symbol twitches or does not follow the track - with the mgl disconnected it looks fine so I assume the data from the mgl to the Garmin is incorrect.
If anyone has any good ideas I'd love to hear them

I have a 175 connected to a MGL Odyssey and had the same problem.
I solved it by unchecking the ARINC lateral steering pass through in the Odyssey ARINC setup menu.
Mike
 
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