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Adding second GRT display

Maverick972

Well Known Member
I am considering adding a second GRT unit to my RV7, currently I have a single HXr.

Looking at the current line up what GRT unit makes the most sense to add seeing as the HXr is discontinued
 
What functions are you looking for?
Similar to the HXr? The horizon 10.1.
An emergency backup unit? One of the Mini’s.
 
How much panel space have you? If you have lots of panel space but limited budget, the Sport 10.1, otherwise the Horizon 10.1.

The new glass in GRT's EFIS products is substantially better than previous glass. I have a Mini-X, HX and Sport EX. The Mini and Sport EX both have LED backlighting which is both brighter and provides a much wider dimming range, plus there's no warm-up time in the cold weather.

One of the other considerations of course is how much other equipment you want to have interface with the new display. The Sport products have limited serial ports, but one can buy the serial interface expansion products fairly cheaply so that really isn't a significant limitation but buying a Sport then buying the port expander then buying mapping/synthetic vision gets you up into the Horizon price range. Defining what you want the box to do will give you a really good place to hang your hat when making the right product decision.

Oh, one other thing... with two displays you will be able to connect the inter-display link and have data sync from one display to the other. Stuff like baroset where you change it on one display and it automagically updates the other display. A nice workload saver. The inter-display link isn't well documented - RS232 TX from EFIS1 goes to RX on EFIS2 then TX from EFIS2 goes to RX on EFIS 1 to form a communications loop.
 
While you can use the RS232 links for communicating between displays, the newer (Hx and newer) also have an ethernet link for that function as well - faster and can save you an rs232 port.
Edit added: Thanks to Mark, below: I should have said you can use ethernet between Hx and newer Horizon displays. Not Sport or Mini's.
 
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Bob - is the ethernet port functionality on the Horizon 10.1 what is referred to as the "high speed" option for an additional $150? Meaning to interconnect two Horizon 10.1 displays via ethernet would cost an additional $300? Do I have this right?

What other kinds of devices would you connect to the ethernet port?

Just trying to educate myself on the Horizon 10.1 units.

Thanks.
 
The newer displays do not all have the ethernet link. Ethernet started with the HX product.

From GRT's product descriptions on their current website:
Sport 10.1: Six serial ports in and out, and dual USB port,s [sic]
Sport EX & Horizon EX: Three serial ports in and out (optional with six), a USB port, and a dedicated magnetometer port, allow for great flexibility within your panel design. An optional ARINC 429 interface can also be added, while still retaining all serial ports, for connectivity with IFR GPS navigators, such as the G430/650/750.
Horizon 10.1: Horizon 10.1 includes 12 serial ports, in and out, and dual USB ports. Multiple display units are coupled via Ethernet.

So... Any EX EFIS and the Mini in any flavor do NOT have ethernet. Ethernet appears to be available in only the Horizon 10.1. Nothing else connects to the Ethernet port, it's just for linking between Horizon 10.1 units.

The high speed option is one which uses an airspeed sensor capable of and accurate across a higher speed range than standard.
 
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