G3X to Axis

[Astro John]

I purchased a Hard IFR panel from Bearhawk with dual G3Xs. I knew the AXIS was coming out, but planned to keep the G3X for a while.

That didn't last long. SNPS (Shiny New Panel Syndrome) kicked in, and I sold my G3X panels, which are finding a new home in a Bearhawk 4! There is a funny story about how that went down, but I'll save it for another day.

I was a complete Garmin newbie. Peter at Bearhawk provided me nice upgrade schematic with everything I need to do. After receiving my Axis panels, I started collecting all of the tools, connectors, and wires that I would need. I bugged Peter on numerous occasions with questions. I'm sure at some point, he regretted ever building my panel in the first place. Thanks Peter!

I had a few times where progress stopped when I realized I didn't have everything I needed, and had to order something. A competent installer, with everything on hand, could complete the process in a day. I crammed all of that into about 4 weeks.


Here is the breakdown of what I did:

I had to create 4 High Speed Data Bus Cables to go with the one already installed. I have built plenty of network cables in my time, but this was the first time I have worked with shielded cable, and shield drains.

Instead of the single power cable, I had to splice in 4 power connections the Axis uses and also add 4 more ground wires.

This was the first time I ever worked with DSUB connectors. Installing the pins is easy, but removing them is a bit tricky. Luckily, there were only 4 that I needed to remove, plus one more that I installed in the wrong spot.

The only other thing I had to do hardware wise was swap out the config module on my Primary display, and add a config module on the second display.

I have a GTN750xi, and I decided to update the software on that. It recommended a wipe of the config module. I figure I had to redo the configuration of the panels, so I might as well do the whole system.

It was a crash course on HSDB, Can bus, RS-232, and Arinc429. I spent quite a bit of time researching issues and going over schematics. In the end, I got it going, and learned a whole lot in the process. It was a nice diversion from the build. Now I just need an airplane to put it in.

One benefit is that I now have a much better understanding of how my panel was built and works. I am completely confident that I can troubleshoot and fix any issues that may arise in the future. I am glad I did it, and glad that I didn't wait until it was installed in the airplane.

 

[jaredyates]

Thank you for sharing your experience. I really appreciate Peter and I'm glad he's doing all that he is!

Something that I have found, which you may or may not, is that I'm very good at what I call hiding my own easter eggs. I've done three panels now and each time I finish the job with a very thorough understanding of how it all went together. Then a year or two or three later when it is time to tweak something or add a new wire, I find out how much I forgot in that time. Take good notes, label your wires, and maybe you'll find success when you decide to add a new gadget later. I can't imagine owning/operating/maintaining a plane in this modern age without a very thorough understanding of the electrical architecture and all of the avionics. It's an area that deserves our efforts.

The shift away from craftsmanship in our community is a mixed blessing in that in enables growth into a new set of customers that were previously not accessible. But it also means there will be increasing numbers of planes out there in the hands of builders who didn't have to figure out a lot of stuff that the builder used to have to figure out. It's like the joke about which is the better pilot, the Navy guy who can land on a short pitching carrier deck on a rainy night, or the Air Force guy who made life choices so that he doesn't have to. I won't say it's worse or better, but it's different.

 

[Astro John]

Good advice. I purchased a label maker that can do shrink wrap, and labeled all the wiring I added. Peter did a very thorough job labeling everything he did, and included very detailed schematics.

Part of my research was just to look at the way he did things on my panel and try to match it. I did use different color cable ties, just so I can quickly identify my work vs. his.