Whats a decent used transponder that can be upgraded to ADSB Out?

[lndwarrior]

I don't have a glass panel, basic steam gages only. I want to buy a used transponder that I can later connect to in ADSB out system.

Can someone recommend a decent used transponder that would have this capability?

TIA
Gary

[flightlogic]

Gary, you don't upgrade transponders for ADS-B.
You just get a UAT (universal access transceiver) for ADS-B from any of a variety of manufacturers. They either listen for the transponder code, or hook directly to it via serial link. There is a ton of reading material on line that will explain it for you. But, shopping for an antique transponder would be a waste of money. You can also buy a brand new modern xponder that has ADS-B capability built in. A few thousand $ for those.

[lndwarrior]

Let me re-phrase.

I want to buy a used transponder that i can later use with an ADSB out solution. I dont want to spend the money on a new Tx if i dont have to.

I have seen a number of posts that suggest that this is possible.

I am trying to learn which common Txs that come up for sale may be appropriate.

Ive seen refernce to some of the Garmin ones that may work for me. I am trying to figure out which model numbers would work.

It is my Understanding that there are a number of transponders that are being replaced due to panel upgrades that would still work for my situation.

I am trying to do this as inexpensively as possible.

[ALagonia]

I have a Garmin GTX 327 in my 9. I just ordered the GDL82 from Stein Air. The GDL82 will connect to my GTX327. That will give me ADS-B Out at a very reasonable cost. Installation is very straight forward.

[Canadian_JOY]

Oh boy... here we go!

Just about ANY functioning transponder capable of doing Mode C altitude reporting will work as the basis for an ADSB-Out solution IF you want to use a 978 UAT device. The 978 UAT device "sniffs" the squawk code and altitude of your Mode C transponder and uses that information in the 978 ADSB-Out data stream.

That's one method of gaining "out" compliance and many folks see it as the most economically-effective method because they can keep on using their ancient Mode C transponder.

Another method uses a fancier transponder, what we call a Mode S Extended Squitter (Mode S-ES). This type of transponder doesn't require that you add a 978 UAT device. Instead, the Mode S-ES transponder, when coupled to an altitude encoder source and an appropriate GPS position source, IS your ADSB-Out solution.

You need to educate yourself a bit before deciding which route you wish to take, 978 UAT or Mode S-ES. Once you've decided which route you want to take, then start looking at the specifics of which equipment to buy.

The SEARCH function here is a great way to get some good data points drawn from the experiences of others. Spend some time reading and learning, then come back with questions once you've got yourself up to speed.

[lndwarrior]

Originally Posted by Canadian_JOY

Oh boy... here we go!

Just about ANY functioning transponder capable of doing Mode C altitude reporting will work as the basis for an ADSB-Out solution IF you want to use a 978 UAT device. The 978 UAT device "sniffs" the squawk code and altitude of your Mode C transponder and uses that information in the 978 ADSB-Out data stream.

That's one method of gaining "out" compliance and many folks see it as the most economically-effective method because they can keep on using their ancient Mode C transponder.

Another method uses a fancier transponder, what we call a Mode S Extended Squitter (Mode S-ES). This type of transponder doesn't require that you add a 978 UAT device. Instead, the Mode S-ES transponder, when coupled to an altitude encoder source and an appropriate GPS position source, IS your ADSB-Out solution.

You need to educate yourself a bit before deciding which route you wish to take, 978 UAT or Mode S-ES. Once you've decided which route you want to take, then start looking at the specifics of which equipment to buy.

The SEARCH function here is a great way to get some good data points drawn from the experiences of others. Spend some time reading and learning, then come back with questions once you've got yourself up to speed.

Thanks for taking the time to explain. I appreciate it!

[krwalsh]

Originally Posted by lndwarrior

Can someone recommend a decent used transponder that would have this capability?

TIA
Gary

You can get a Garmin GTX-330 and upgrade it to Extended Squitter for $1400 ( I think it used to be $1200).

Lately it seems like the going price of a used GTX-330 is in the $800 range.

[larosta]

Would a used King KT76 or KT76a with an altitude encoder work. Looks like a lot of these will be available for a couple of hundred dollars as aircraft are upgraded to Mode S installations. It would give you a mode C (978 MHz) transponder. At a later point you could add one of the 978UAT ADS-B out solutions like the uAvionix or Garmin GDL82.

Put the FAA rebate on this and you are 2020 compliant for around 1
$1500. At some point pick up a spare KT76 and you are good to go for several years.

-larosta

[oaklandaviator]

I believe the FAA rebate this time is only for certified systems. So, just the expensive all in one new transponders.

[larosta]

I believe that a NEW Garmin GDL82 installed and fed by an existing (read used) Mose C transponder meets the requirements for the rebate.

https://www.faa.gov/nextgen/equipads...ion/equipment/


- larosta