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GRT EFIS controlling radio and transponder - useful?

rv8ch

Well Known Member
Patron
Just curious, is it worth it or useful to have my EFIS control my transponder or radio? I'm sure that there is some value, but having not experienced this first hand, I'd appreciate any feedback from someone that has configured this and either found it useful, or didn't find it useful. I have a GRT Sport EX and a Trig TY91 and a TT22, and they both have the standard control heads, and it seems like the GRT can also act as a control head with some wiring and configuration.

Thanks!
 
Quite honestly I don?t know of any value in it, except to free up panel space. I do have a remote mounted TT22 controlled by the HX. I ran an ?ident? wire to a switch on the stick, to make things easier for me.
 
I had mine wired that way to my GTR200 until adding ads-b and needing the serial port on my Sport. I had never used it and didn't miss it. I am now upgrading to an HXr and will have it wired again, just because I can, but doubt I will use it much.

Chris
 
I don?t use it but I believe the grt EFISs can also automatically load in frequencies for destination airports as you approach them.
 
My first generation avionics in my RV-12 has the capability. It is ?cool? to see the frequencies transfer over, but I don't ever remember using it in flight. Just as easy to crank the numbers in directly. But we pilots do love our gadgets, and that is reason enough! 😉
 
Panel space

would seem to be the biggest advantage. I've had several Sonex flyers ask to include control over remote COM radios and transponders in my system. RVs have a good bit more panel space, so it's generally less of an issue for us.

The other useful function is (as several have mentioned) is automatic frequency selection. I'm not sure how useful anyone else's system is, including GRT. I've been using it for a while in my EFIS and I would call it a "nice to have" feature, but definitely not a requirement.
 
Just curious, is it worth it or useful to have my EFIS control my transponder or radio? I'm sure that there is some value, but having not experienced this first hand, I'd appreciate any feedback from someone that has configured this and either found it useful, or didn't find it useful. I have a GRT Sport EX and a Trig TY91 and a TT22, and they both have the standard control heads, and it seems like the GRT can also act as a control head with some wiring and configuration.

Thanks!

The HXr remote control works great. Being an old guy I was hesitant to have everything remoted, so I remoted some and have knobs and buttons for others.

Using the HXr to change freqs or transponder codes is as easy as directly touching a control head, so if I had to do it over again, I'd remote the items I have panel mounted - the audio panel and Comm 2.
 
I have an HXr, com1 & Transponder panel mounted. Com2 remote due to a space challenged panel. The panel radios are in front of the right seat. I find it much more convenient to use the efis to change freqs on the radio I am currently talking on instead of reaching in front of my pax. I always use the xponder panel to set codes and squawk.

I did not think I would use the efis to control com1 but wired it up anyhow. I didn't use it at first but after carrying a pax who was sitting there playing on her ipad the whole flt, I found it much easier to use the efis for the frequent changes.

I also have an 8000B audio panel with a remote swap button.The HXr also has a swap button. I put the audio panel swap near the HXr swap and am still confused. One swaps freqs on the selected audio device in the efis and the other swaps com1/2. When I want to swap both T and R, I use the swap button. But to listen to the efis on com2, I use the audio panel buttons.

I would caution you about trying to use all the switches available on a control stick grip.

The F-16C has 14 switches on the stick & throttle. Only one does avionics functions. The PTT. I shudder when I hear someone say he has the start button on the stick. That is a "ruin your day" button push waiting to happen. A frequency change or swap button on the stick should be labeled the "lost com" button.

JMHO.

Your mileage may vary.
 
I have the HXrs and a Garmin GTR-200. I find it useful to have the EFIS push freqs over to the transceiver. For example, from the EFIS map page, I can select an airport, then from the Waypoint Details, hit the FREQ softkey then SET COM/NAV. I don't use the other control capabilities.

In the case of the GTR-200, it's an additional wire between it and the EFIS to let them talk.
 
GRT Remote control of COM/XPNDR

What RV-14E said. I have GRT Hx connected to an SL-30 and use the EFIS to push frequencies over to the SL-30 almost exclusively. Very nice to be able to access the database in the EFIS for all the nearest available frequencies when enroute. No need to fumble with a chart. Although I don't have it, remote control of the XPNDR makes sense too. Vary rarely have a need to change the sqawk code.

I have the Infinity grip with a toggle switch for flaps up/down which I find very convenient. Coolie Hat for trim, trigger sw for the PTT, push buttons for AP Disconnect, SL-30 Frequency Toggle and Remote Ident.
 
I didnt wire in any of the remoting functions with my HXrs mostly because all my radios etc are smack in the middle, so didnt see the need to touch the screen when I can touch the buttons on the box instead. I can def see the usefulness if you have to remote something due to panel space. I think there may be some discussion of an HXr taking out boxes that its linked to, but I dont see that as likely over a serial link.... I believe I have mine set up to load my SL30 from my GNS480 for radio freqs tho, and I can see the usefulness of that.....
2vanm2h.jpg
 
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Much like Mani, above, my centre stack of radios is manually controlled. I have the TT22 transponder and thought long and hard about using the GRT Mini-X to control it. In the end I stuck with the dedicated TC20 control head for the transponder and am glad that I did.

The only reason I say this is because I really like having the Mini-X set up as my permanent PFD which I touch only to adjust brightness. Having it sitting there with PFD info always available gives me the confidence to do whatever I want on the HX and no matter how badly I might goof up the button-ology of the HX, I still have a rock-solid PFD beside it by which to fly the airplane.

Yeah, I know, I'm sounding very old-school. Heck, I am old, but I also have learned my limitations. Juggling buttons on multiple EFIS screens just isn't wise for me to do in a high workload environment.
 
remote control

I have a Trig TT-22 remote transponder that I control with my GRT Mini-AP. It is very easy to operate. (and I'm old too)
 
When I built the 8 I wanted two GRT 10.4 HxR screens in the panel but with the tandem layout, space is at a premium. My solution was a single sheet of aluminum and controlling the TT-22 remotely. In the pic you can see the transponder interface on the right side of each screen. Very easy to operate and saves panel space.

hug5rn.jpg
 
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