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Which GRT Displays are These?

Pilotjim77

Well Known Member
I purchased these units and have been trying to read up on them, but I'm not sure which units they are. I did call GRT but I think they are kinda busy right now as I have not heard back. I don't know if these are Sport, Horizon or what I might need to purchase to get everything up and running. I'm planning to buy the ADS-B package and the EIS package from GRT to go with these.


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These look like the original GRT Horizon units - pre- the HS, then HX, versions. I don?t know if they can or cannot display ADSB data, you?ll need GRT to tell you.
 
Looks like the original EFIS system, called the WS I believe, in addition you have the XM weather module, and one screen has the GPS module, and the other has ARINC. The ARINC is good for autopilot use, allows maximum function with TruTrack at least.

Should be a great setup, and if you later upgrade you will find the wiring harness will plug right into the newer screens-------not sure about the new 10.1 unit with the built in AHARS.

Looks exactly like what I had in the RV 10 before I upgraded to the HX setup.
 
Those are original WS displays. The same as are still flying in our airplane, just because we haven't gotten around to replacing the panel.
Your serial numbers are very similar to ours. We've failed (to the dumpster) two of them so far. Not much fun when you're IFR, don't do it with those serial numbers.
That XM module, yeah, had it, didn't work out for us, ever.
My ahrs is only a few ahead of that one.

I would call that package a great, cheap, day VFR only solution.
 
Those are original WS displays. The same as are still flying in our airplane, just because we haven't gotten around to replacing the panel.
Your serial numbers are very similar to ours. We've failed (to the dumpster) two of them so far. Not much fun when you're IFR, don't do it with those serial numbers.
That XM module, yeah, had it, didn't work out for us, ever.
My ahrs is only a few ahead of that one.

I would call that package a great, cheap, day VFR only solution.

Definitely VFR only with this setup. I also have a Garmin 696 I would like to put in the panel, which I think would give me a good backup navigator along with the panel page in the event of an EFIS failure.
 
You know Scott, you?ve been whining about your WS displays since I worked at GRT, which was... 5-7 years ago. ;) Figured you?d have upgraded to at least an outdated HX by now!

Those are original WS displays. The same as are still flying in our airplane, just because we haven't gotten around to replacing the panel.
Your serial numbers are very similar to ours. We've failed (to the dumpster) two of them so far. Not much fun when you're IFR, don't do it with those serial numbers.
That XM module, yeah, had it, didn't work out for us, ever.
My ahrs is only a few ahead of that one.

I would call that package a great, cheap, day VFR only solution.
 
You know Scott, you?ve been whining about your WS displays since I worked at GRT, which was... 5-7 years ago. ;) Figured you?d have upgraded to at least an outdated HX by now!

I?d say he has been blessed with foresight - he waited long enough that GRT?s latest boxes will fit in the WS cutout.
And the HX is not outdated - just obsoleted, since the OEM display manufacturer no longer supplies displays in that size.
 
I?d say he has been blessed with foresight - he waited long enough that GRT?s latest boxes will fit in the WS cutout.
And the HX is not outdated - just obsoleted, since the OEM display manufacturer no longer supplies displays in that size.

Good point!! :)
 
There is nothing in these to keep them from being used IFR. I do not agree with the commenters that think these are not capable. They are, as evidenced by me and others.
Can they fail? Yes. But that can be said of every other IFR technology on the planet. Plan your panel for failure scenarios and its not an issue.

And to answer the ADSB question, yes they will display weather and traffic.

Scott, the EX is fantastic. GET ONE.
 
You know Scott, you?ve been whining about your WS displays since I worked at GRT, which was... 5-7 years ago. ;) Figured you?d have upgraded to at least an outdated HX by now!

So true! It is nothing but a personal problem of making it happen :).
Truth be told, there is only one original WS (out of 3) left in our panel. I added an early HX quite some time ago, and recently a G5 to replace a failed WS.
 
There is nothing in these to keep them from being used IFR. I do not agree with the commenters that think these are not capable. They are, as evidenced by me and others.
Can they fail? Yes. But that can be said of every other IFR technology on the planet. Plan your panel for failure scenarios and its not an issue.

And to answer the ADSB question, yes they will display weather and traffic.

Scott, the EX is fantastic. GET ONE.

Thank you for your comments. I sold these to the buyer and had used them in my RV10 for several years shooting coupled RNAV, ILS, VOR approaches with Trutark. They do everything my AFS 5800 does with the exception of Touch. As is with any EFIS, they all have advantages and disadvantages. I still miss some of the features in GRT that I do not have on my AFS. I also yanked my XM subscription in favor of ADSB on the same old EFIS.
 
I ordered the EIS and the ADS-B package today from GRT as well as wiring harnesses. (Delivery of ADS-B is after first of year).

Can anyone tell me how I might turn the display units on? I don't have any 25 pin d-sub connectors, and I don't know which pin to attach the power and ground leads to from a 12 volt batt. I've looked on the GRT website, but I can't find a drawing or diagram of which pin is for power/ground.
 
So, I'm looking at page 3 of the Horizon Cable Description document on the GRT website. It appears that pin 14 is for primary power and pin 17 for ground. This is on the female d-sub connector on the back of the display unit. I'm hoping someone with more knowledge than I can confirm. ;)
 
Power

So, I'm looking at page 3 of the Horizon Cable Description document on the GRT website. It appears that pin 14 is for primary power and pin 17 for ground. This is on the female d-sub connector on the back of the display unit. I'm hoping someone with more knowledge than I can confirm. ;)

You are correct. Connector A Pin 14 = Primary Power In and Pin 17 = Ground. Pins 15 and 16 can also be used for power. Pin 18 is keep-alive power for the internal clock.

Skylor
 
I am finding the wording in the GRT wiring documents confusing. This is what it says for the connectors that are on the back of the display units:

"Display Unit Connector A Description:
Mating Connector: 25-pin Female D-sub (Instrument has 25-pin Male D-sub)"

"Display Unit Connector B Description:
Mating Connector: 25-pin Male D-sub (Instrument has 25-pin Female D-sub)"

So, I'm understanding this to mean that the Male d-sub on the back of the unit is Connector A. Is this correct? None of the connectors are marked or labeled A or B. (Confused because this would make the connector on the right A and the one on the left B, which seems counter-intuitive.) There are no pictures or diagrams in the GRT document. I just don't want to connect power to the wrong pin.
 
"Display Unit Connector A Description:
Mating Connector: 25-pin Female D-sub (Instrument has 25-pin Male D-sub)"

"Display Unit Connector B Description:
Mating Connector: 25-pin Male D-sub (Instrument has 25-pin Female D-sub)"

My take is "Instrument has 25-pin Male D-sub" means you will see the pins on the instruments and "Instrument has 25-pin Female D-sub" means you will only see the holes on the instrument plug.
 
I don't know what "instrument" refers to. Is is referring to the display unit or to whatever the other end of the harness connects to?
 
Connector A = Male

I don't know what "instrument" refers to. Is is referring to the display unit or to whatever the other end of the harness connects to?

Connector A is indeed the male connector located on the right side of the display unit when looking at the back. "Instrument" = EFIS Display Unit.

Skylor
 
Read the manuals

All of the manuals and documents you need are on the GRTavionics web site. Select Support then EFIS manuals and softwear, then HS/WS EFIS displays, then Horizon WS, there you go. Scroll down to find manuals, cable descriptions, wiring diagrams etc.
 
All of the manuals and documents you need are on the GRTavionics web site. Select Support then EFIS manuals and softwear, then HS/WS EFIS displays, then Horizon WS, there you go. Scroll down to find manuals, cable descriptions, wiring diagrams etc.

+1+1+1
To the OP: more product ?defects? are due to mis-wiring than anything else. Some manufacturers won?t warrantee equipment with a user-built wiring harness. Applying 12 volts to the wrong pin can destroy internal components.
1. Get the manuals
2. Get a magnifying glass so you can read the tiny pin numbers.
3. Check by counting from pin 1.
4. Insert pin (with wire crimped on)
5. Check again that it?s in the right hole.
6. Count from pin 1 again, you can?t be too careful.

These boxes can do a lot of things - which means that there are lots of options to set up. You absolutely need the manuals (there are 3; installation, setup, operation).
 
All of the manuals and documents you need are on the GRTavionics web site. Select Support then EFIS manuals and softwear, then HS/WS EFIS displays, then Horizon WS, there you go. Scroll down to find manuals, cable descriptions, wiring diagrams etc.

+1+1+1
To the OP: more product ?defects? are due to mis-wiring than anything else. Some manufacturers won?t warrantee equipment with a user-built wiring harness. Applying 12 volts to the wrong pin can destroy internal components.
1. Get the manuals
2. Get a magnifying glass so you can read the tiny pin numbers.
3. Check by counting from pin 1.
4. Insert pin (with wire crimped on)
5. Check again that it?s in the right hole.
6. Count from pin 1 again, you can?t be too careful.

These boxes can do a lot of things - which means that there are lots of options to set up. You absolutely need the manuals (there are 3; installation, setup, operation).

Thanks guys. I have actually read through the GRT Cable Description document numerous times, and, as I stated in post #16, I am confused by a portion of the wording on one of the pages and am looking for clarification. Rob and Skylor have provided guidance, but I am still waiting for confirmation from GRT.
 
You have it correct in your post 16. But download the manuals, they have pictures. The reason the left-right (B-A) sequence seems odd is that it can only be ?normal? on one side. To the techs building the box from the inside, connector A is on the left. Same thing for the connectors: if seen from the pin side 1,2,3,... run left to right, then they will run right to left on the reverse (wire side), and also on the pin side of the mating connector. But left to right on the wire side of the mating connector. Confused? Everyone is. You cannot be too careful.
 
Pictures of WS/HS

You have it correct in your post 16. But download the manuals, they have pictures. The reason the left-right (B-A) sequence seems odd is that it can only be ‘normal’ on one side. To the techs building the box from the inside, connector A is on the left. Same thing for the connectors: if seen from the pin side 1,2,3,... run left to right, then they will run right to left on the reverse (wire side), and also on the pin side of the mating connector. But left to right on the wire side of the mating connector. Confused? Everyone is. You cannot be too careful.

The problem is, none of the manuals have actual pictures of the back of the WS or HS displays (at least that I could find). The WS and HS displays have the same connector layout as each other but are different from the HX/HXr displays. The connector pin assignment is the same, however. Tomorrow I can take a picture of the back of an old HS that I have on hand and physically identify the connectors as well as the pin# layout. I have been working with the GRT displays on my plane (flying since 2010) including building all of my own wiring harnesses and bench test harnesses since ~ 2006 and I have never had a wiring issue so I do know my way around them quite well.

Skylor
 
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You have it correct in your post 16. But download the manuals, they have pictures. The reason the left-right (B-A) sequence seems odd is that it can only be ?normal? on one side. To the techs building the box from the inside, connector A is on the left. Same thing for the connectors: if seen from the pin side 1,2,3,... run left to right, then they will run right to left on the reverse (wire side), and also on the pin side of the mating connector. But left to right on the wire side of the mating connector. Confused? Everyone is. You cannot be too careful.

The problem is, none of the manuals have actual pictures of the back of the WS or HS displays (at least that I could find). The WS and HS displays have the same connector layout as each other but are different from the HX/HXr displays. The connector pin assignment is the same, however. Tomorrow I can take a picture of the back of an old HS that I have on hand and physically identify the connectors as well as the pin# layout. I have been working with the GRT displays on my plane (flying since 2010) including building all of my own wiring harnesses and bench test harnesses since ~ 2006 and I have never had a wiring issue so I do know my way around them quite well.

Skylor

Thank you Bob, Skylor, and Rob. I did receive a phone call from GRT a while ago confirming that connector A is on the right. From there, I felt confident to connect pins 14 and 17 to a battery. Both display units turned on fine and are working well!

Bob, you are right, it can certainly be confusing, but I'm glad to be learning about it, and I'm grateful for all the help available here.

As Skylor mentioned, there are no pictures of the back of the units or of the connectors in any of the manuals. I went through all of them thoroughly (User, Setup, and Installation, as well as all of the Cable Description documents and Example Wiring Diagrams). While there are dozens of pictures of screen shots in the User Manual, there are no pics of d-sub connectors or of the back of the units anywhere.
 
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