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Dynon Skyview and Trig TX56X integration

Frogman208

Active Member
Dynon Skyview and Trig TX56 integration

Hi Vanation,

So I thought I’d give some feedback on the new Trig TX56A COM/NAV radio integration with the Dynon Skyview. I’ve seen a few posts within various forums asking the questions on compatibility and installation so below are my thoughts and minor issues that I’m trying to figure out. The Trig replaced my 1 year old, trusted second radio Garmin 200. The replacement only took us about 4 hrs to complete which included installing the Archer Antenna in the wing tip. Actually, probably the hardest part was running the RG400 cable through the wing and center section. The form and fit was almost identical to the Garmin 200 (size and weight), so swapping trays was relatively easy, no cutting panel like I would have had to do if I went with the Garmin 255. I was already using the Dynon Serial Port #3 for the Garmin 200, so the wiring was relatively easy on the Comm side but had to build a harness for the Nav side and connect to Port #3. Basically the form, fit and wiring is extremely easy as far as integrating into the Dynon Skyview. Lets talk about compatibility. The Trig understands the Garmin SL-30 “AND” Gamin 255 A/B protocols, so in Dynon skyview port (in my case) #3, I chose the Garmin 255 A/B protocol ($PGRMC and $PGRMV) which set the speed at 9600 bps and immediately the Trig started talking to the Dynon. Next is the CDI configuration that must be set up. Trig has a sub menu that you go into and push the “type” of CDI you would like. The choices are Converter, Resolver, Serial and Internal. When the Trig is talking to an external EFIS, the serial is the choice you are supposed to use, same function in the SL-30 when you chose CDI choice-“none”. So now I dial in the VOT testing frequency (we have one at the airfield), and the CDI comes up- GREAT- but if I stop turning the knob, the skyview CDI disappears. Ok, that doesn’t work correctly, so I double check all settings and even change protocol in Port #3 to SL-30 ($PMRRC and $PMRRV) but still no change to the skyview CDI needle. It will appear if I spin the knob but disappear if not actively turning the knob. So this is what I currently had to do for it to work appropriately. Like I said earlier, in the Trig sub section, you can choose Converter, Resolver, Serial or Internal. When I choose “INTERNAL”, the Dynon Skyview CDI works accordingly with a few caveats.

The skyview CDI needle WILL NOT come up if you dial in NAV frequency on the Trig, you get the ID (voice and automatic) BUT YOU HAVE TO HIT THE OBS button on the TRIG. This activates your Skyview CDI for the rest of the flight. You can change freqs, go from VOR to ILS. You can turn the CRS knob on the Dynon or Trig as both work. You can also monitor the standby Nav FREQ on the TRIG and it will get you the standby bearing. I wish that part showed up on the Dynon ‘bearing bugs’ since it is showing “NAV stby” as a Nav source but so far I cant get that to work. With all that said, it tracks VOR’s, ILS/GS really well in this configuration as well as autopilot. In this mode (INTERNAL), I believe the Skyview is just mimicking what the TRIG is displaying on its own screen, that is why you have to activate the OBS mode on the Trig. I’ll update more as I get information back from Dynon and Trig on this compatibility. Hope that helps those that are looking for the combination I have. I’ll post pictures later today. Last note- Like others in on this forum, I’m in IFR training so that is why I needed an additional “Nav” source. I only had the Garmin 355 and was just flying overlays for VOR/ILS’s, now I can track via NAV capability.
 
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Picture of Trig Installed

Here is what the install looks like for reference.
 

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I’d start by contacting Dynon. I have a different system (GRT Hx/SL30) but it works with ‘serial’ as the output format from the SL30. It also shows the ‘monitored’ VOR as an RSI needle superimposed on the HSI, which works very nicely on approaches.
I vaguely recall that the SL30 has some sort of fail-safe mode, where it stops sending data out if the data in from the EFIS is lost. Might check your RS232-in lines to the nav, as well as the out lines. Make sure the Dynon is constantly sending OBS data to the nav, not just when you touch the obs knob.
 
Talked with Dynon

Thanks Bob, yep already talked with Dynon. They are waiting on the unit that Trig is sending them for testing. I'm running some Diagnostics for them with the SL-30 protocol and 255 protocol. I believe this is why Trig states, the TX56 is "like" the SL-30 for protocol. No worries on my end, I knew what I was getting into. The Trig TX56 is really good quality, better than I expected. Just working out the bugs with it being so new.
 
I suspect TRIG will sell a lot of these. I'm putting one in the new RV-10 project to go with the GNC 355 TSO GPS navigator.

Carl
 
Is there any difference in functionality between protocols? Why use the the GNC vs the SL30 selection?

I’m planning a TX56 too so I’m very interested in the write up.
 
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From what I can tell with 2 days of flying both protocols, the answer is NO (maybe), from operator perspective no, not sure about the data box. Neither protocol work when the Trig CDI indicator is selected to "serial" and both work when Trig CDI indicator is selected to "internal". After this morning flight, my procedure is after engine start, dial in the local VOT on the TRIG and push the Trig (OBS) button. This energizes the Skyview CDI for the entire flight. I ran VOR's, LOC, ILS's, and autopilot coupled/uncoupled. The Dynon skyview picked up the Localizer, turned on the autopilot, armed the VNAV and got the locked and coupled ILS w/glideslope. Here is another shortfall if your running the Garmin GNC 355 series and completely separate NAV radio. . The Skyview only shows one 'source' at a time (not including RMI bugs on CDI), so if I use green needles (NAV radio), I'm not able to show my magenta lines from my GPS overlay on skyview (I know spoiled). So I track via green needles and watch the Garmin 355 flight plan screen as backup. Helped verify my track with the green needles. On some of the approaches, if I can't get the GPS approach overlay loaded in time, I go strictly by green needles and time. For those that don't know, the GNC series loads all the different types of approaches ie..LOC, ILS, GPS. You cant legally fly the ILS/LOC with GPS but its great as backup/verification to your needles.

All in all, until Dynon gets there hands on the Trig TX56 and works the small bugs, this will work to get me thru my IFR testing.
 
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I found the answer to the protocol. The TX56 instal manual section 6.2.9 states the GNC protocol is the preferred choice.
 
Scott,
Great, timely post! Saving pennies but as soon as I can I’ll be buying the Trig. My stack will be identical to yours. I have the AFS ACM so will be curious how that integration works. So far, love it! Keep us posted.
 
Update status

Guys,

Just wanted to give an update to this thread for those who are going the TRIG TX56 route. I've been in weekly contact with TRIG on the integration of the Dynon/TRIG TX56 combination. What a fantastic company for customer service which is hard to come by nowadays! They have replicated my setup (Dynon Skyview and TX56) in the lab hooked up via RS232 and have duplicated the same behavior as noted in the original post. At this point, Dynon Skyview is just replicating on its CDI needle what the TX56 NAV function is requesting. Basically, the TX56 is acting as a standalone unit and projecting course on the skyview CDI. It works for training as long as I hit the OBS button on the TX56 first, then the Skyview CDI needle comes alive.

I just got an update from TRIG that they have a software update that is just about ready for release. This same behavior apparently also happens with the Garmin G3X for those using Garmin. When the software is released, the configuration and integration should be as advertised in the installation manual. About the only change, I will probably see is I wont have to hit the TX56 OBS button prior to green needles coming alive on the Dynon Skyview CDI. For those who are wondering, the TX56 overall has been rock solid for communication and navigation. I've hit VOR's that are 50 miles away and the signal has been solid. Since I've getting ready for my IFR checkride, I've been using the green needles more than the GPS (Garmin 355). The Dynon autopilot has tracked both green needle and GS on ILS approaches. Will let everybody know when software update has been released.
 
Hey Scott,

Thanks for the great updates on your TRIG T56 and Dynon integration. I'm also looking at replacing my Garmin GTR200 with a TRIG T56 to provide a Nav radio to my Skyview HDX.

Couple of questions. Does the Trig tray fit in the exact panel space as the GTR200 tray, it seems to bee the same size? Or was some modification required? Is the quality of the Trig com radio seem as good as the Garmin 200? And finally, could you share your wiring setup so I could see the work required to rewire the com and add the nav to my Dynon system.

Thanks,
Paul
 
Easy swap

Hey Paul,

I actually dry fit the TX56 in the Garmin 200 tray and it fit exactly the same so no panel cutting. That is one reason I chose the TRIG TX56, all I had to do physically was swap trays and re-wire the sub-D harness. I reused the Garmin 200 wire harness, just re-pinned to the new sub-D for the Comm side and added the harness for the Nav side via RS232. It actually took longer to run the archer antenna coax cable then anything else. I dont have the actual pin-out handy but the TX56 Installation manual has the example for Dynon/Garmin pin out and configuration. The quality of the Trig TX56 is impressive, its Garmin quality or better. The sub-D's, wiring and accessory parts are top quality, very detailed Installation manual. I've been flying alot at night and its the only display I dont have to either decrease "dim" or increase "dim". The photosensors on the Garmin and Dynon "dim" to dark for my tast but the yellow readout in the TX56 is always crisp and not bright, really good at night. All the garmin radios have "green" readouts but the TRIG yellow readouts seem more clear to me but that is just my opinion. Bottom line- really liked the Garmin 200 (that reminds me I need to put it up for sale) but the COM/NAV Trig is amazing. Its my primary Nav source right now in training. Hope that helps.
 
Scott,

Thanks for the quick reply. Glad to hear that the swap was straight forward and didn't require any modification of your panel. Also, good to hear that the radio works well and has similar quality to the Garmin. Or better per Carl's experience. That's good news on my decision to get the Trig!

Re-pining the com side from the Garmin 200 to the TX56 seems pretty straightforward based on the pinout info in the TX56 install manual. However, the Trig install manual and Dynon 3rd part connection manual seem to indicate that all the SL30 or GNC 255 Nav data communication is over the two RS232 (TX & RX) pins to the Dynon Serial ports (RX & TX respectively). The Trig RS232 pins are both on the TRIG'S com D-sub connector. It seems the only connections needed on the Trig Nav D-sub are power and ground. Is that how you wired it or am I miss-reading the install manuals?

Thanks,
Paul
 
Has anybody gotten the TX56 to talk to a Dynon? I have both. I have the trig set as Serial and the Dynon set accordingly. I get the Nav and Com frequencies displayed on the Dynon, but I can't push frequencies to the Trig. I also get no CDI needles on the Dynon. Has anybody else gone through this process and got it working? If so, what was your procedure?

Thanks!
 
Great talking with you Jesse. Hopefully Trig will get the software update complete soon. I just emailed for an update from Trig so hope to hear soon. Glad you got the Trig functioning with the HDX.
 
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