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Transponder: starting from scratch

Inhot

Well Known Member
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Hi Guys, I might be buying my first RV, it's a 6 and it has never had a transponder installed. My goal is to make it ADS-B compliant. I'm looking for recommended solutions. I'd like to say cost is not an issue, but I'd be lying. I'm looking for the most economical, reliable solution. Ideas?
 
The least expensive route to consider is a used transponder (e.g. GTX-327 or 330) with a uAvionix TailBeacon or SkyBeacon, for ADS-B out. Spend a little more money for the TailBeaconX with AV-20 or 30 and you get a new transponder and a nice mini EFIS in the panel.
 
Maybe not the least expensive but I went with the Appareo Stratus ESG and it works great. I liked that it was an all in one unit. Also it has a pass-through connector on the back that you can use with an ads-b in unit and only have one antenna on the outside of the plane.
 
The "beacons" are okay but the GDL 82 is less expensive and rock solid. The reliability of a direct connection via coax while avoiding wireless interface or nav light mods. I have installed a few of each, beacons and GDL 82's. I would suggest best bang for the buck is a used GTX 327 combined with the GDL 82 UAT out. UAT will also give your the privacy advantages of anonymous mode. If you want an EFIS put in a straight AV-30E (awesome) and ignore the ponderous Tailbeacon X.
 
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Forgive me if you already know all this, but here’s a mini tutorial:
ADSB-OUT (you send a signal out) is now required in all US airspace where a mode C transponder is required. ADSB-IN (you receive data) is not required, anywhere. Of course the IN data is what’s most useful to you.
There are two forms of OUT data, either a mode SES transponder transmitting on 1090 MHz, or a Universal Access Transceiver (UAT) transmitting on 978 MHz. If you have a UAT you must also have a mode C transponder, to operate in airspace where they are required. A mode S-ES transponder is both a transponder and an OUT device. You are only allowed to use one OUT device at any given time, so no one installs both. Plus/minus: most UATs can be configured to hide your real N number, if you don’t like Big Brother (or your neighbors, who can easily access the data with a computer) watching you. At this time mode SES transponders always send N numbers, although there is talk of changing that. Note either system broadcasts your real N number if you are in contact with ATC getting flight following, ifr, etc (anytime your squawk code is not 1200). Mode SES is mandatory above 18,000’, if that interests you. No foreign country uses UAT, if that’s a concern.
Adsb-IN is optional. Many UATs include it in their box, most transponders do not. You may listen on one or both the frequencies mentioned. If you are within range of a ground station, it will relay to you the missing traffic (if you only can receive one frequency), as well as non-adsb aircraft detected by ATC radar. Ground stations will send you weather but only on 978 MHz. If you cannot receive that you won’t get wx. Now...
Your transponder will need a source of pressure altitude. Your ADSB-out device will need an ‘approved’ gps data source. [edit: your adsb-out must also use the same pressure altitude source as your transponder.] You will need some way of displaying IN traffic and wx data (panel mounted screen, iPad via wi-fi, etc). Whatever you choose, you need to verify that everything talks to everything it’s hooked up to. For example a Garmin WAAS navigator is an approved gps source. But it outputs the required data in a propriatary Garmin format, ‘ADSB+’. You need to verify that whatever OUT box you use can read that data. Bottom line here, you need to consider your entire panel, the whole system.
My recommendations: if you want all-new, it’s a no-brainer. A Trig mode SES transponder for under $2K, a compatible encoder (almost any modern efis, or a stand-alone device), and a $500 approved gps source from GRT. (If your new aircraft has a 430W the Trig can read and use that. May need Garmin software upgrade if it’s old enough, about $100). For IN (optional), there are many choices under $1K but you need to consider what display you will use, and are they compatible.
Complication. If you are willing to buy used equipment, the equation changes. So many owners have pulled good mode C transponders out and replaced them with a mode SES, that the used market is depressed. You can buy a good, used GTX-327 mode C for $400. At that price, a used mode C and a new UAT are competitive, and some cheaper, than my SES recommendation above. Of course this route involves more installation labor (if someone is being paid) and you need two antennas. But often IN is included in the package. And sometimes the gps is included too. So look at your whole panel, decide what you want/need/can live with, go from there.
 
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Maybe not the least expensive but I went with the Appareo Stratus ESG and it works great. I liked that it was an all in one unit. Also it has a pass-through connector on the back that you can use with an ads-b in unit and only have one antenna on the outside of the plane.

This is the same route I went, I'm very happy with it.
 
Another vote for Trig. I've installed Trig transponder and GRT Safe Fly 2020 GPS source on 3 aircraft and wouldn't hesitate to do same again.
 
Talk to Terry Gardner down The road at KTTA. He runs an Experimental completion center there and is very knowledgeable on the RV line of aircraft. I have done a number of avionics designs and installations for him and he can give you a bunch of input from his and his customer feedback.

His hangar/ shop is next to the Wings of Carolina Flying Club at the south end of the field.
 
I have a used Stratus Appareo that was just removed (working perfectly, just over a year in service, replaced with Dynon in a full panel upgrade) from our Cessna 172 sitting in my office at home looking for a new home. Let me get some pictures of it this evening and I'll send them to you.
 
A local avionics shop says used GTX-327 is the way to go.
There are a lot on the used market with all the big $ panel upgrades, so price is good. They are rock solid and will last forever.

Did that in my 7 with a GDL-82. Piece of pizza.
 
i like easy and simple. for me it is worth a few bucks for the easy install. i would go with a gtx335 with the garmin encoder. two wires, two coaxes. and mount the two antennas. done. less than 3k. second would be the egs.

bob burns
rv-4 n82rb
 
Thanks to all. Great information. I’m coming from 40 years of military and airline flying with only a few hundred hours of G.A. and gave never owned an airplane. This is all new to me, the info you provided today will be basis of my decision. I’m going to price out the various options and consider the work required for installation in order to decide. I’ll post once I do. Thank you!
 
I had a GTX-327 in the panel so the GDL-82 was the way to go. Note - this provides ADS-B OUT only. I already had IN, via a Garmin GDL-39 talking to a tablet via bluetooth.
 
echoUAT/SKYFX

echoUAT/SKYFX with any old transponder (GTX320A, 327...) is another option.

You get ADSB-In for free.

But probably can't beat the used Stratus 1090ESG from airguy for just ADSB-Out

Finn
 
Only in the US. Should you wish to fly your aircraft internationally (Canada, Mexico, etc.) you should (shall) require a diversity transponder for satellite based ADS-B. Regulations on this are being finalized, but it is easier to plan for this now rather than having to upgrade later.

Current economical choices are uAvionix TailBeacon-X, but because it doesn't have a built in strobe, that is a consideration. Encouraging signs from Jim Weir (Kitplanes) who is designing a dipole transponder antenna that should work with any mode-s/es transponder. https://www.kitplanes.com/ads-b-eh/

My bet is that for non-class B, the dipole will be more than adequate and we are hoping for one of the antenna design or transponder firms to put one on the market.
 
I Bought It!

It's mine now!: I still haven't finalized my transponder/adsb choice. I'm going to meet with Terry Gardner this week and hash it out (thank-you Noel). I'm leaning towards the Skybeacon X coupled with the AV-30E. No panel mods required and lots of capabilities built into the AV-30.

Thanks for all the inputs.
 

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Vortex Generators

Thanks. There's a thread from several years ago about how to remove VGs. There didn't seem to be much of a consensus as to how to remove them. I might just go with "if it ain't broke, don't fix it." 😎
 
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