Ironflight

Ironflight

VAF Moderator / Line Boy
Mentor
I just installed an HX in my DU #1 slot last evening, and took it for a quick flight. My first impression is....AWESOME! Very crisp, smooth graphics, nice contrast, and a highly detailed terrain database. The screen is nice and bright, just like on the HS, and better than the WS (The original GRT EFIS), which was plenty bright, even in a sunlit RV-8 cockpit. The HX has the same screen as the HS, but the processor is faster, with more memory, and supports Synthetic Vision software, and it is clear that GRT has spent a lot of time getting it right. Todd told me that there are parts of it that he’s still working on (runway representation for instance), but the natural terrain is great. I remember how quickly features were added to the original WS software once the box was released, and I think that cool stuff is going to keep appearing in the HX as the basics work and they have time to work on refinements.

You must remember that I am living on the Gulf coast, so there is no relief to speak of in the terrain for about 100 miles - but looking at the water down by the coast, the outlines are really remarkably accurate and detailed - right down to the intercoastal waterway, and little man-made canals on Galveston Island (what's left of it!). I am planning on flying to LOE out in El Paso next weekend, and should get to try it out in mountainous terrain then - I'll try to remember to record some demos, and get some video. The shading in the Synthetic Vision appeared to show stream beds here on the coastal flats that correlate with real creeks – it is THAT good!

Installation was really simple, took me about 30 minutes, and I was able to keep my RAIM GPS module. I had it on DU #1, and an ARINC on DU #2. Since the HX has built-in ARINC, I put the GPS on DU#2, did a couple of quick config changes, and all was operating well. Yes, the HX has an internal cooling fan, and Todd from GRT recommends an external fan as a backup - I hope to engineer something this week before the trip. But overall, if you have HS's, the HX will drop right in. Make sure to back up the config before taking out the old unit, then upload the backup to the replacement, and you should be ready to go. Operationally, there is nothing new – if you can operate the original EFIS, you can operate the HS, or HX – there are just more displays available, and more goodies….The HX and HS seem to play together perfectly, with data interchange seamless, just as if they were identical units.

Can't wait to go flying with it again today - but I think we're taking the RV-6 somewhere, and it has those "other" systems in the panel...oh well, we'll get more time on Sunday!

Paul
(Volunteer GRT Beta Tester)
 
Last edited:
Hi Paul, do you have any pictures of your HX combined with the older DU-2? I'm curious about the dimensions now.

Several things jump out at me when I'm thinking 'plug and play', since I really don't feel like doing a major over haul behind my panel. Remember, I'm thinking replacing only one, and using the HX as DU-2 for my Colorado terrain.

Looks like the width of the HX is slightly less than my HWS (original Horizon 1), but it's higher (and deeper). I know the hole in the panel needs to be enlarged in height, should be no problem in my case, but was it an issue to hide the previous screw holes and have clearance to add new without trashing your panel and paint job.

You said in your post the HX has it's own ARINC module, I have one on my DU-1. Would I just leave it unwired on DU-2? No advantage to having 2 modules. Would this cause integration problems?

I also see that you mentioned the HX has an internal fan which is probably why it is deeper, and you say they also recommend additional cooling. Did that cause problems, I think my AHRS is mounted just like yours (I probably copied your pictures), and there is not a whole lot of space back there.

As always, thanks for your time.

Jim Gray

531-lrg.jpg
 
n747jg said:
Looks like the width of the HX is slightly less than my HWS (original Horizon 1), but it's higher (and deeper). I know the hole in the panel needs to be enlarged in height, should be no problem in my case, but was it an issue to hide the previous screw holes and have clearance to add new without trashing your panel and paint job.

You said in your post the HX has it's own ARINC module, I have one on my DU-1. Would I just leave it unwired on DU-2? No advantage to having 2 modules. Would this cause integration problems?

I also see that you mentioned the HX has an internal fan which is probably why it is deeper, and you say they also recommend additional cooling. Did that cause problems, I think my AHRS is mounted just like yours (I probably copied your pictures), and there is not a whole lot of space back there.
Click to expand...

Hi Jim,

When I modified the panel for the HS's (going from the WS's), I didn't have to do any width changes to my holes, and in fact, re-used the bottom two rivnuts - they lined up perfectly in width to the new units. Height should be the only thing that changes, along with the vertical position of the rivnuts/nutplates that you use to hold the DU's in place (I use rivnuts for this because they are quick and easy to install, and handle low load in this location). If you are going to put the HX on the bottom, you could enlarge that hole .25" top and bottom, and slide it in!

With regards to the ARINC - yup, you could just leave it unwired on DU #2, and not change a thing (leave it disabled in DU #2 software). An alternative is to see if you can get credit for the one you have, and swap the cable to the new unit - I certainly don't speak for GRT, but they (or someone else) might take it off your hands - that's a chunk of beer money for sure!

Yes, the HS/HX's are deeper, and in order to get the HS to fit with my AHRS, I took the backshell's off the DIN connectors on the lower unit. With appropriate strain relief, there isn't any problem with this according to my wiring guru's at work.....The backshells probably caused a third of an inch interference with the AHRS, and they are much longer than they need to be.

I just got back from another flight with the HX, and it is still quite amazing - really fast and smooth.

Paul
 
Another HX quicklook (long)

Last Friday, received two HXs to replace H1s in my RV-7A. Only paper work in box was invoice. No pin definitions or other info provided.

Physically, units are heavy (3.4#) and seem to run much hotter than H1s. Little fan runs all the time.

Bench check: Ran both units to check setup and make minor tweaks. Linux OS with MUCH more memory (looks like 1GB) so redraws should be faster. Imported settings I had save from H1s and the import worked. Activated Ethernet link and disabled serial ports that had been used for display link on the H1s. Found that the ARINC ports on the HX were configured low-low on the unit that replaced the H1 that had ARINC configured low-low. However, the other HX (replaced an H1 with no ARINC) came up high-low, by default I guess. Found serial ports 7 and 8 but no idea what pins they are assigned. The setup menu only shows 10 entries but that?s probably good because the font is small and the limited number of lines makes reading easier. Reset oil is still at the bottom of long graphical engine display menu where it is easy to find but tedious to get to. My H1s had been wired for audio since early 2004 and had been mute so was hoping to find some entries related to audio in the HX setup; found none. Found setup choices to control page choices, tape styles, indexes, and visibility (on MAP) but otherwise the setup is the same as H1 ver 32. Played demo files to check video. The two HXs to stayed in sync better than the H1s during playback, probably because inter-display data was now on the Ethernet.

Installation in panel: Panel hack went well. Before even getting in cockpit, made two ??-wide strips of 032 with 6-32 plate nuts spaced for the HX mounting holes because I knew that the sides of the panel opening was already riddled with screw and rivet holes from the H1s. After increasing the height of the opening 1 inch, drilled out old #6 plate nuts and then matched drilled the HX to the panel. Put the strips behind it using the new holes to index them and riveted them in place. The connectors are oriented differently and I found that it was more difficult for me to mate the connectors with the HX?s parallel configuration. With the H1s, was able to mate the connectors before installing the units. With the HXs wasn?t able to mate one connector on the lower unit until it was in the panel.

Power up in aircraft: HXs and AHRSs saw each other. Display was certainly crisper but essentially the same one that was on the H1. Symbols and text need updates to take advantage of higher pixel density. With the old H1s, I was able to get the GRT GPS (GPS2) to lock in the hangar but the HXs do not support that module so I didn?t have MAP info. Crappy wx so didn?t roll RV out to get GNS 480 GPS lock. Hindsight: could have put GNS in sim mode and driven HX that way. Oh, well. Removed the units to play more with GPS at home.

GPS: I knew that the GRT GPS would not work before I received the units and had talked to Mark at GRT about it. Initially, he suggested that I buy a not-yet-ready RAIM GPS that GRT would be selling. I wasn?t too excited about that option after spending $425 for the now-unsupported GRT GPS. Besides, I?ve been flying the H1s for >4 years with a GNS 480 and haven?t seen one RAIM problem yet. Mark gave me the pinouts of the GRT GPS (5v, 12v, ground, and serial I/O). At home, I powered the GPS module and connected ground and serial out to an HX. No luck. I then tapped the serial that goes from the Byonics GPS dongle that feeds my APRS transmitter and ran the tap and ground to the HX. It worked. The $69 Byonics GPS is WAAS enabled and needs only 5v which can come from the 4.8 volt source on the GRT EIS. A simple, cheap, and available backup GPS. Many other GPS sources should work as well. Emailed Mark on Saturday re the GRT GPS failure but no reply yet.

Only issue I had at home was the time required for the MAP to update from TERRAIN to SHADE. It took a lot of time for the red to disappear. Also, the house is at 5,880? AGL a valley below at about 5,000?. With the H1 terrain, it was red under my feet and not red in the valley. With the HX, everything was red with terrain selected. Could be that the AHRS altitude is needed vice GPS altitude.

Won?t fly until Wednesday when I?ll fly some instrument approaches. Expect functionality to be the same but hope to see less "loading" and faster XM refresh.

John Nystrom

RV-7A, N7VD, 450 hours
RV-3B, N3NU, 774 rivets.
 
GRT GPS and HX

The GRT GPS module is designed to plug into the back of a Horizon 1 (H1) MFD. The pins in the H1 provide 5v for the GPS, 12v for serial, ground and serial I/O. The same pins are used for the H1 ARINC module. The HX has integral ARINC and simply has no place in which to plug the module.

I figured that if I could provide the power the module requires from another source, I should be able run the GPS serial out to one of the HX serial input ports configured for 4800 baud and NEMA0183. I've tried twice to do that. The first time, the pinouts I got from GRT were from the perspective of the EFIS and what I thought was serial out from the GPS was actually serial in so had no luck. The second time, the serial was wired properly and the HX saw the port but the GPS never saw even one satellite. The HX said GPS2 was "Flagged" and after 10 minutes, I gave up and went to plan B to get backup GPS data.

The only reason I went through the wiring exercise was to see if I could get some use out of a module I already had. For me, it didn't work. As I indicated in an earlier post, I was able to tap into another NEMA source, the inexpensive, WAAS-enabled GPS, I use for my APRS; and it works great as a backup to my GNS 480.

John Nystrom
 
Great info John. Looking at the screenshots, I would agree that they could do more with the software now that they have the new, higher rez display. But that's Ok, better to promise less and overdeliver than the opposite.

TODR
 
Quick and Dirty video....

OK, rather than start a new thread, I'll just add this on here:

I got the opportunity to fly the HX out to LOE this weekend, which meant getting into terrain where the highest element is NOT the highway overpass! This quick video was shot while approaching the Guadalupe Pass from the east. (The "nose" of the Guadalupe Mountains is known as El Capitan, and just behind it is Guadalupe Peak). I shot this last night while sitting in the cockpit and playing back recorded data - the YouTube Version is pretty fuzzy - sorry, we'll do better later.

I switched between map and PFD views to show a little context for those unfamiliar with the area - this thing is remarkably sharp and detailed, runs fast and smooth, and is an absolute star in poor visibility!

I'll try to post more when I get the chance, but for those that wanted something right away....

http://www.youtube.com/watch?v=QCWf8-rhfzU

I'm sure that those who crowded around the airplane to watch the demo on the ramp at LOE will agree that it is WAY better in real life!

Paul
 
Hummmm

I have the 8" on order......

How is the HX with maps, iFR plates....?

Whats with the yahoo group...?
 
Sticky1 said:
I have the 8" on order......

How is the HX with maps, iFR plates....?

Whats with the yahoo group...?
Click to expand...

I don't know anything about IFR plates on the GRT systems - don't know what they are working on, but I kind of like having a system that does what it does, and doesn't try to be everything in one box....(just my personal prejudice).

The GRT Yahoo group seems alive and well to me Sticky - I get messages every day!

Paul
 
You must log in or register to reply here.