ADS-B & Existing WAAS GPS

Flyhound

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I've been looking at the prices for adding ADS-B out to my plane and all of the units I've found have their own WAAS compliant GPS built in. I already have a WAAS GPS (Garmin 430) with an RS 232 port. Have any of you found a transmitter that will work with the position signal from an existing WAAS GPS for a lower price? I don't need to buy hardware with a TSO'd ADS-B in solution because the portable ADS-B in unit I'm currently using (Dual XGPS 170) works just fine. I'm looking for the lowest cost ADS-B out I can get. What I've found so far seems to have hardware I don't need with the attendant cost of another antenna and more complicated installation costs.
 
You will have to install another antenna under the airplane. No getting around that. Install will be in the $2000 range or more regardless of what unit you buy.

If you already have the Garmin product, and you have going to spend the money on ADSB, I'd highly suggest the GDL88. You say you dont want the ADSB in, but you are also saying you use ADSB in on your portable. Having traffic overlay on your 430W is rather nice among the other features.

So what I'm trying to say I guess is if your trying to nickle and dime your way through ADSB, your really not going to save a lot in the end.

In your case, wait and see what is coming down the pipe. I'd like to see a panel mounted out only unit. That would reduce install costs a little. But if a captive environment, I really don't see anything ground breaking, nor do I see costs dropping.

And as a side note, IF you decide to go with an IN solution, only a Garmin product will talk with your Garmin. The protocols are proprietary so Navworks or Avidyne won't do anything for you.
 
No, that isn't correct. A GDL-88 is to give you ADS-B IN & OUT. I read the original post that OP wants OUT only and has a 430W. If that is the case, you can get a GTX-330ES transponder and you'll have the OUT only. That is my plan because I, just like you, already have a portable IN solution.
 
ahkahn said:
No, that isn't correct. A GDL-88 is to give you ADS-B IN & OUT. I read the original post that OP wants OUT only and has a 430W. If that is the case, you can get a GTX-330ES transponder and you'll have the OUT only. That is my plan because I, just like you, already have a portable IN solution.
Click to expand...

Yup

Best way to do it
 
Prices to swap out a Garmin 327 for a 330 es are being quoted at around 6 K with the trade in 327.
 
ahkahn said:
No, that isn't correct. A GDL-88 is to give you ADS-B IN & OUT. I read the original post that OP wants OUT only and has a 430W. If that is the case, you can get a GTX-330ES transponder and you'll have the OUT only. That is my plan because I, just like you, already have a portable IN solution.
Click to expand...
....and if your goal is to stay in the US and not leave the country and not fly higher than 18,000....the GDL-88 will work for ya just fine. It's a UAT device.

On the other hand if you need those things....then you'll want the "ES" transponder that transmits on the 1090 freq.

The best fit for me, since I have a WAAS GPS, is the King KT-74, ES transponder. It's a slide in replacement, with minor wire-up, to the 76A boxes. It's also $2,500 for an ES box.
 
ahkahn said:
No, that isn't correct. A GDL-88 is to give you ADS-B IN & OUT. I read the original post that OP wants OUT only and has a 430W. If that is the case, you can get a GTX-330ES transponder and you'll have the OUT only. That is my plan because I, just like you, already have a portable IN solution.
Click to expand...

So a GTX330ES is $3995 and a GDL88 is $3995. One is ADSB Out only and the other is both out and in. A portable In, although very useful is not the same as an installed in capability.
 
ahkahn said:
No, that isn't correct. A GDL-88 is to give you ADS-B IN & OUT. I read the original post that OP wants OUT only and has a 430W. If that is the case, you can get a GTX-330ES transponder and you'll have the OUT only. That is my plan because I, just like you, already have a portable IN solution.
Click to expand...

Me is confused... What are you saying is incorrect? I know he wants out only, so I suggested he wait for more options to hit the market, e.g., panel mounted out only.

With what he has, going 330ES is stupid because its short changing his options and cost the same than the UAT installed. He has a 430W.

That's like buying a car without A/C because it has windows that roll down but the power window option costs the same as what the A/C does. Makes no damn sense.
 
frfly172 said:
Prices to swap out a Garmin 327 for a 330 es are being quoted at around 6 K with the trade in 327.
Click to expand...

I'd keep shopping, look on the used market.

Also being a early adopter is not a good idea $
 
Unit74 said:
Me is confused... What are you saying is incorrect? I know he wants out only, so I suggested he wait for more options to hit the market, e.g., panel mounted out only.

With what he has, going 330ES is stupid because its short changing his options and cost the same than the UAT installed. He has a 430W.

That's like buying a car without A/C because it has windows that roll down but the power window option costs the same as what the A/C does. Makes no damn sense.
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I hear you. The part that I was talking about being incorrect is installing another antenna. Correct for GDL-88, but not correct for GTX-330.

I think your solution vs. my solution depends on his transponder. If he has a GTX-330, like me, it's a $1500-$1700 upgrade with virtually no labor. Even if he needs a new transponder, while the GTX-330ES is priced comparable to a GDL-88, A GDL-88 requires significantly more labor for wiring, antennas, and connections. So all in you're up to $6000 or more for a GDL-88... assuming it is even compatible with his existing transponder, which it needs to be. But yes, I agree he will get more functionality... so it may be worth the extra money.
 
Sounds about right. My shop, Tomlinson's In Pine Bluff, AR is doing the GDLs for $5k installed. My last call, they were scheduling into Jan 2016 though!!!

Ouch.
 
To answer the OP, the only ADS-B OUT solutions that will work with his Garmin 430W as the position source, today, are Garmin products: GDL-88 and the GTX-330ES. Garmin doesn't play nicely with others - they use proprietary data formats as I understand it.

If he doesn't do Class A airspace and doesn't care about having traffic & WX on the 430W (which only the GDL-88 can provide) then I'd go with a FreeFlight RANGR TX with the position built in - that's still way cheaper than any of the Garmin solutions. He'd get traffic and WX on his portable and saves probably $3k+ over either of the Garmin 'solutions'.

Caveat emptor: I know from various contacts that Trig and BK are working on, if they haven't already received in some cases, STCs to have their 1090ES transponders (required for Class A after 2020) use the Garmin 430/530 and/or GTN series as position sources. Those transponders are way cheaper than the GTX 330ES. Just something to think about if you do Class A.
 
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Don't forget install costs Petro......that sticker price looks nice till the final bill is ready for invoicing.
 
petrolero said:
.

Caveat emptor: I know from various contacts that Trig and BK are working on, if they haven't already received in some cases, STCs to have their 1090ES transponders (required for Class A after 2020) use the Garmin 430/530 and/or GTN series as position sources. Those transponders are way cheaper than the GTX 330ES. Just something to think about if you do Class A.
Click to expand...

Both the Trig TT31 and Bendix King KT74 transponders are STCd for ADSB-out with Garmin GNS GPS units as the position source. They both use the guts of the Trig unit, but with different face plates. If you have a KT76A transponder installed now and a gray code altitude encoder, the new units can use the old tray for a basic ADSB out install. It will require a $100 airspeed switch and a couple of wires run between the GPS and the transponder. And maybe a new coax to the existing transponder antenna if the old cable is not of adequate quality.

They really seem to be the best value so far. Even if you never intend to go above 18000 ft.
 
bkspero said:
Both the Trig TT31 and Bendix King KT74 transponders are STCd for ADSB-out with Garmin GNS GPS units as the position source. They both use the guts of the Trig unit, but with different face plates. If you have a KT76A transponder installed now and a gray code altitude encoder, the new units can use the old tray for a basic ADSB out install. It will require a $100 airspeed switch and a couple of wires run between the GPS and the transponder. And maybe a new coax to the existing transponder antenna if the old cable is not of adequate quality.

They really seem to be the best value so far. Even if you never intend to go above 18000 ft.
Click to expand...

Lol... "It is Trig guts!"

makes me think of this:
https://www.youtube.com/watch?v=nb_R1VZqLcE
 
bkspero said:
Both the Trig TT31 and Bendix King KT74 transponders are STCd for ADSB-out with Garmin GNS GPS units as the position source. They both use the guts of the Trig unit, but with different face plates. If you have a KT76A transponder installed now and a gray code altitude encoder, the new units can use the old tray for a basic ADSB out install. It will require a $100 airspeed switch and a couple of wires run between the GPS and the transponder. And maybe a new coax to the existing transponder antenna if the old cable is not of adequate quality.

They really seem to be the best value so far. Even if you never intend to go above 18000 ft.
Click to expand...

Correct and the STC for the GTN series is coming soon.
 
I have a 1976 Skylane with a GNS 530W, KT-76A Transponder, and TRANS CAL D 120 P 2 T Encoder. I'm also looking for ADSB-OUT and am happy enough with Foreflight/Stratus for ADSB-IN, but I might agree with the comment that panel mount ADSB-IN might not add much to the installed price.

Is the KT74 really an easy replacement, or do you also have to add extra boxes to get 2010 compliant?
 
182driver said:
I have a 1976 Skylane with a GNS 530W, KT-76A Transponder, and TRANS CAL D 120 P 2 T Encoder. I'm also looking for ADSB-OUT and am happy enough with Foreflight/Stratus for ADSB-IN, but I might agree with the comment that panel mount ADSB-IN might not add much to the installed price.

Is the KT74 really an easy replacement, or do you also have to add extra boxes to get 2010 compliant?
Click to expand...

Replacing the KT76A with a KT74 should be relatively straight forward and will get you compliance if the STC IM is followed. Your installer adds an airspeed pressure switch to determine ground/air status and a serial interface between the GNS530W and the KT74 is added. I would also suggest you add the ARINC429 between the KT74 and the GNS530W for TIS. Although TIS is not TISB, it is better than nothing and will display traffic in many areas around the higher density airports. More than likely, the coax to your transponder antenna should be replaced because of age and you should consider replacing the antenna if it is warranted, particularly if you currently have the cheap short wire antenna with the ball on the end. They are known to break off and short out the transponder.
 
My next panel mount ADS-B display is going to be an iPad mini in an Airgismos mount and a Stratus for a source receiver. Complete with Synthetic Vision and a backup IFR panel.

ADS-B-out with be a 1090 transponder with ES. Brand TBD, but probably not Garmin.
 
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>> And as a side note, IF you decide to go with an IN solution, only a Garmin product will talk with your Garmin. The protocols are proprietary so Navworks or Avidyne won't do anything for you.

Uh, no. My NavWorx box talks nicely to my two Garmin boxes. See NavWorx' website for the table of all the boxes they can talk to.


Paul
 
Personally, I want something like the KT-74 or 330ES transponders with their build in ADS-B OUT capability, plus an additional ADS-B IN functionality. A bluetooth interface, to feed a tablet would make it perfect.

I simply don't like the complexity that comes with all those different boxes for transponder / ADS-B OUT / ADS-B IN or possibly even a portable receiver, sitting on top of the panel, powered from the cigarette lighter...

Edit: I just saw that the Lynx NGT-9000 offers this functionality: http://www.l-3lynx.com/models.htm
 
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having traffic & WX on the 430W (which only the GDL-88 can provide)
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The FreeFlight Ranger displays traffic on the 430W, I'm not sure about weather. It's doesn't save any money over a GDL-88 though, and uses its own GPS.
 
To the OP: I just went through an ADS-B Out only upgrade this past week. Unless I missed it, you never mention what kind of a transponder you currently have. As a couple others mentioned since you already have a Garmin WAAS GPS and Garmin doesn't talk well with others, you'll have to take a look at "the last Out piece" you're missing: the xpndr. I just upgraded my GTX330 to the ES version and it was $1700 from Garmin. If you have a Garmin xpndr, I'd recommend upgrading it, having a shop properly program the required info into it, sign off on your 91.413 and call it a day.
 
John Collins said:
Replacing the KT76A with a KT74 should be relatively straight forward and will get you compliance if the STC IM is followed. Your installer adds an airspeed pressure switch to determine ground/air status and a serial interface between the GNS530W and the KT74 is added. I would also suggest you add the ARINC429 between the KT74 and the GNS530W for TIS. Although TIS is not TISB, it is better than nothing and will display traffic in many areas around the higher density airports. More than likely, the coax to your transponder antenna should be replaced because of age and you should consider replacing the antenna if it is warranted, particularly if you currently have the cheap short wire antenna with the ball on the end. They are known to break off and short out the transponder.
Click to expand...

With the most recent firmware for the KT-74 you can install it in an ADS-B out configuration with the 530W using the existing KT-76a tray...as long as you have an altitude encoder with Gray Code parallel interface to the transponder and you do not choose to install a TIS (aka TIS-A, aka not ADS-B TIS-B) traffic to the 530w. That saves you the cost to purchase and install the new tray.

If you have an altitude encoder with a serial interface or need an ARINC429 for the TIS-A traffic, then you will need the new tray for the connections.
 
Has anyone installed the 74 in place of their 76a and set it up without enabling the ADS-B out? I have a new 74 and would like to start using while waiting to upgrade the rest of the avionics and then enable ADS-B out, later this year.
 
tmyers said:
Has anyone installed the 74 in place of their 76a and set it up without enabling the ADS-B out? I have a new 74 and would like to start using while waiting to upgrade the rest of the avionics and then enable ADS-B out, later this year.
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That should be all covered in the IM.
 
I have read it cover to cover and everything is about hooking it up for ADS-B out. In the check out section 4 the manual does have comments like IF INSTALLED verify the squat switch and IF INSTALLED verify the GPS position Source. Similar language in the set up section but as for a simple slide out slide in I haven't found it.

Vendor says just slide out slide in, 337, static, altimeter and transponder check will be necessary to be legal.

Working with a local shop waiting to hear what they say and was curious if anyone else had made the switch prior to putting the GPS in their aircraft.
 
I think I'll wait five more years and see what the landscape looks like then.

Until then... see me and avoid!

And I'll do likewise like we've been doing for the past .... forever.
 
tmyers said:
Has anyone installed the 74 in place of their 76a and set it up without enabling the ADS-B out? I have a new 74 and would like to start using while waiting to upgrade the rest of the avionics and then enable ADS-B out, later this year.
Click to expand...

Look at the Trig TT31 installation manual. The KT-74 is a TT31 with a different skin.

http://www.trig-avionics.com/library/TT31-00455-00-AP.pdf

It contains information on both Mode S and ADS-B configurations.
 
I dead the trig manual and it very plainly explains that if the 76A was working a 74 will work
 
tmyers said:
I dead the trig manual and it very plainly explains that if the 76A was working a 74 will work
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my understanding, since this will be the path I'm taking, is that a new mount is required for ADS-B "out". The 74 has an additional connector that is not supported by the old mount.

If all you're after is mode "s"....the old mount will work as a slide in replacement.
 
Checkout_my_Six said:
my understanding, since this will be the path I'm taking, is that a new mount is required for ADS-B "out". The 74 has an additional connector that is not supported by the old mount.

If all you're after is mode "s"....the old mount will work as a slide in replacement.
Click to expand...

All the signals required for ADS-B are available in the original tray and connector for the KT74. You have to add the additional wires, but the tray will work as is.

However, if you have a GNS430W/530W or other compatible GPS, you are going to want to install the ARINC 429 signals for TIS. TIS is not TISB and does not require ADS-B to be functioning as it is a Mode S feature. The TIS signals require the KT74 tray with the second connector. The other signal available in the second connector is a serial interface for an encoder. This signal is not needed for a slide in replacement, but a new installation that has a serial encoder will use this signal instead of the parallel encoder input used by the KT76A and already wired in for a slide out-slide in replacement. None of the signals in the second connector are required for an ADS-B slide in/out replacement.
 
nice....I have the 530W...sew, that's prolly why I was thinking that and had it backwards. :D
John Collins said:
All the signals required for ADS-B are available in the original tray and connector for the KT74. You have to add the additional wires, but the tray will work as is.

However, if you have a GNS430W/530W or other compatible GPS, you are going to want to install the ARINC 429 signals for TIS. TIS is not TISB and does not require ADS-B to be functioning as it is a Mode S feature. The TIS signals require the KT74 tray with the second connector. The other signal available in the second connector is a serial interface for an encoder. This signal is not needed for a slide in replacement, but a new installation that has a serial encoder will use this signal instead of the parallel encoder input used by the KT76A and already wired in for a slide out-slide in replacement. None of the signals in the second connector are required for an ADS-B slide in/out replacement.
Click to expand...
 
Thanks John, that is how I was interpreting it. My plan is to install a 430, with 106, and a 155 with 203 which will get rid of most of my Narco stuff. A PA800BT to replace the Narco Audion panel and when this happens the old 76A tray will be replaced with the new one and connectors for the 74.

I still could have the Narco DME but will most likely get rid of it at that time as well.

Thoughts?
 
The level of detail in these responses is making my uninitiated head hurt. I currently have the Garmin GTX 327 Transponder working with my Garmin 430 WAAS GPS. The screen on 430 is too small to make the ADSB in worth much. The cost of the Garmin 330 ES transponder is quite a bit higher than the KT74 from King. Can I mix and match the KT74 with the Garmin 430? If so, that is looking like the best combination of purchase and installation costs. Unit74's comment that their local shop is currently scheduling installations for January of 2016 is a bit on the scary side though! An on-line decision tree for installation options (allowing integration of cost and hardware decisions for a given capability) would be great to have.
 
txflyer said:
I think I'll wait five more years and see what the landscape looks like then.

Until then... see me and avoid!

And I'll do likewise like we've been doing for the past .... forever.
Click to expand...
As much as I'd love to wait until then, I'm based inside the Mode C veil :(
 
Flyhound said:
The screen on 430 is too small to make the ADSB in worth much. .
Click to expand...

I'd disagree. I page out to 20 miles every now and again, then back to the chi screen. If I'm running the map page, the traffic and the trend line is rather nice, especially in busy airspace. Not to mention, "traffic 12 o'clock, one mile" in the headset for when I'm not paying attention.

It has its drawbacks, but it's not a waste on a 430w.
 
Flyhound said:
The screen on 430 is too small to make the ADSB in worth much. The cost of the Garmin 330 ES transponder is quite a bit higher than the KT74 from King. Can I mix and match the KT74 with the Garmin 430?
Click to expand...


Flyhound. To get the ADS-B "in" on Garmin is more than just upgrading your 327 to a 330ES and programming it correctly. That just gets you "out compliant". If you want traffic and weather on your 430 you'll need a GDL-88 that interacts with your 330ES and 430. It'll get the reply from the ground station and display that reply on your 430. Or you can do what I think most are doing and just upgrade only the transponder (with an already WAAS GPS) and be ADS-B out compliant. And then use the in portion on a portable such as an iPad with foreflight and Stratus or iPad with a Garmin GDL-39 and Garminpilot. I think after you see the price tag on the GDL-88, it'll at least make you think twice. It did for me and I went with foreflight & stratus. I'd recommend doing some research on source pages and documents for truth data. Also, their is a list (and I can't find it right now) of which transponders work with which GPSs. But a question you should ask yourself: when Garmin or King pushes a new firmware or software update to their product in the distant future & you or a shop install it, will it still work with another brand?
 
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