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GRT WS to a Horizon EX upgrade

gfr56md

Member
Greetings
anyone out there upgraded their GRT WS (vintage) to the Horizon EX (high-resolution)?
Regards Jerry
 
We did it in January.
- Great upgrade. The difference in resolution is very nice.
- I like the synthetic vision.
- You will have an internal GPS in each unit.
- Much brighter in than the WS.
- Engine instruments along the bottom of the PFD.
- It was a fairly easy install, though not quite plug-n-play like they advertise. The hole in your panel will work fine, but the bolt holes don't match, so you will have to move your nutplates or whatever is holding your current WS system in. I'm sure they had a good reason for changing the bolt holes, but it sure would have made it easier if they had matched them up for a true plug-n-play replacement.
- The serial ports are in a different position on the back of the units, so you may have to adjust some of your wiring. Mine ended up being just a bit short, but I was able to make it work. Otherwise, it is a direct plug and play.
- Easy set-up by copying your old settings and importing them into the new units.
- IF you have an old transponder, like we did, you may need a grey code adapter to get your EX talking to your transponder. We have a Garmin 320A and without the grey code adapter, we could not transmit mode C. GRT was awesome about making me a grey code adapter to fix the problem and it worked as advertised. Not a difficult instal, but it took a couple of hours.
- GRT's customer support was outstanding. I love these guys.

Overall: A very worthwhile upgrade. The attached picture does not do it justice because we don't have many hills around here to show off the synthetic vision and the digital camera made the picture look pixelated. It's much sharper in real life.

NEW HORIZON EX
IMG_6371_zpsn0grhj1d.jpg

350EA04E-6AB5-475F-8F9A-14F2C0120FC1%202_zpsbu3iaipo.jpg


OLD HORIZON WS
IMG_6233_zps94qruf4o.jpg


MAP MODE
IMG_6376_zpswe7pep28.jpg


ENGINE PAGE
E0F183B1-E768-4DB0-A632-487312E187C5_zpspfq2b65j.jpg
 
Good looking display

Chuck,

Those are real good looking display pictures. A few questions:

1. Did you also upgrade the AHRS if so was it the adaptive AHRS?
2. How about the magnetometer?
3. What about ARINC 429?
4. Did you have one before and if so I understand the ARINC 429 is now a separate unit and requires a separate mounting. Was that difficult to accommodate?
5. Other than an integrated internal gps and better display picture what other advantages have you observed?
6. Do you know whether you could have two G430s both feed external gps information to the EX and be able to select either one individually?

Thanks
 
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1. Did you also upgrade the AHRS if so was it the adaptive AHRS?
- We kept the original AHRS. Works fine.

2. How about the magnetometer?
- We kept the original magnemometer, but had to recalibrate it, though that surprised the GRT guys, so I don't know if you'd need to do that. But if you do, it was easy.

3. What about ARINC 429?
- We did not have an ARINC 429. Not sure what that is for.

4. Did you have one before and if so I understand the ARINC 429 is now a separate unit and requires a separate mounting. Was that difficult to accommodate?
- ??

5. Other than an integrated internal gps and better display picture what other advantages have you observed?
- I'd say the biggest advantages are the brightness of the screen, the synthetic vision and having the engine display at the bottom. I always had a hard time seeing the synthetic approach boxes in bright sunlight on the WS. On the EX, they show up fine. There are also more high speed serial ports. The WS is a perfectly adequate system, but I am very glad we did the upgrade. I'd say its kind of like going from an old iPhone 3 to a new iPhone 6. The 3 will work fine, but the 6 is just better. These displays are just prettier. I guess it depends on how attached you are to your $4000 (for 2). To me it was a relatively cheap refresh.

6. Do you know whether you could have two G430s both feed external gps information to the EX and be able to select either one individually?
- I'm not certain about 2, but definitely 1 and I think you could do both. I have an iFly740 feeding GPS data into the EX via serial port. It is an easy setup. I would imagine you could do both.

Keep the questions coming. I'm was very new to all of this avionics stuff when I installed the new EX, but I'll give it my best shot.
 
. Did you also upgrade the AHRS if so was it the adaptive AHRS?

3. What about ARINC 429?
- We did not have an ARINC 429. Not sure what that is for.

5. Other than an integrated internal gps and better display picture what other advantages have you observed?
- I'd say the biggest advantages are the brightness of the screen, the synthetic vision and having the engine display at the bottom. I always had a hard time seeing the synthetic approach boxes in bright sunlight on the WS. On the EX, they show up fine. There are also more high speed serial ports. The WS is a perfectly adequate system, but I am very glad we did the upgrade. I'd say its kind of like going from an old iPhone 3 to a new iPhone 6. The 3 will work fine, but the 6 is just better. These displays are just prettier. I guess it depends on how attached you are to your $4000 (for 2). To me it was a relatively cheap.

Keep the questions coming.

Well I am really attached to my $4k plus! However I may consider doing an upgrade in stages but first have to address ads-b out compliance. The ARINC 429 module is required (I believe) for the Garmin 430s. Navigation data from the 430s goes through the ARINC while localizor and ILS data come through a serial ports (I believe) but like you I'm not real smart about this electronic stuff.

I would be more interested in doing the upgrade if the EX also supported geo-referenced approach plates like the HXr. Right now I think I'll just hold on to my money for a while and see what the future holds.

The clarity of your pictures does give me envy though!
 
Jim,

The ARINC module is required to get GPS, VOR, LOC & GS info to your GRT. It allows autopilot functions and also the operation of the HSI.

There is a RS232 serial connection from your 430s to GRT but that only gives the GRT GPS position.

You could install a switch or relay to switch between your two 430s and ARINC if you desire - you probably should also switch the RS232 line too so the same 430 is doing all the communication to the GRT.

At OSH last year, I asked Greg, why I should part with $$$ to upgrade my Sport EFIS. He said there really was no reason. No new functionality. If I am happy now, stay with what I have. I think as features are added, the processor and memory in the older EFIS becomes the limiting factors. You already see this in the availability of synthetic vision. It is not available on the older EFIS.

BTW, if you decide to use a Stratux with your Horizon WS, be sure to update to the latest software (35i) for it all to work.

Jim Butcher
 
Jim,

Thanks for the ARINC clarification. I am in the process of hooking my FlightBox (stratux) to my WS right now. I have already upgraded my EFIS software to 35i.

I agree that upgrading is nice but like you said, other than great screen clarity and synthetic vision, there really isn't a compelling reason right now to part with that much money. Maybe GRT will add some other new features later to make it more attractive. The WS is long in the tooth but it's still a great little EFIS.

Maybe some others out there can give Jerry and I some additional reasons to consider upgrading.
 
IIRC the older WS models can't split the screen (???). The new ones can, and with better resolution, so you can show primary EFIS, map, engine data all at once. Upgrade makes most sense for those that have just one WS box now.
 
IIRC the older WS models can't split the screen (???).

Maybe that was an old software issue. My WS units are VERY early ones and with the software available at the time of panel test (circa 2010), they would split screens in all the common ways, with the exception of the engine data banner at the bottom since that is a resolution feature.
 
Mounting the EX vs the old WS mounts

I purchased the EX Horizon a few months ago and have finally had time to start the installation. I have a WS Horizon currently.

I determined that the new mounting positions for the EX were going to be perfectly in the wrong place in relation to the #6 nutplate rivets for the WS.

The following shows the interference.

888634863597c83cc1d3f7.jpg



This should be true of anyone that used nutplates on the original installation.
Since I used aluminum bodied nyloc nutplates (NOS), I had a chance of drilling and tapping the mess without any other mods, if the rivet did not come loose. If it was a steel nutplate, I think it would have to come off and be replaced with a nut or a custom nutplate.

I made a drill jig to hold the drill in position as it penetrated the mess.
Below, it is screwed into position on the WS mounts.

799318829597c83cc1d72a.jpg



Here is the drilled new hole. The CAD model is pretty close. You can see the outline of the nutplate rivet.

1431925794597c83cc1da1b.jpg



Lastly, a blurry image of the nutplate from the back of the panel.
All 4 holes tapped OK. Rivets stayed tight (for now),

794573046597c83cc1de25.jpg



I made the jig on my mill. I want to drill my #2 WS screen position for future upgrade and then I will consider letting it go to roam around the country as a traveling tool. It will only work for you if the original WS mounts are dead on accurately positioned. If there is slop from a clearance hole/screw/nut mounting method, I would not use it. It is made of 6061 so it will not last too terribly long as the jig holes will wear quickly.

PM me.
 
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