Results 1 to 10 of 15

Thread: Installing a transponder and ADS-B, Instructions?

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1

    Join Date
    Jun 2018
    Location
    ATL
    Posts
    49

    Installing a transponder and ADS-B, Instructions?

    I'm looking to buy an airplane and many of the experimental I am looking at do not have transponders or ADS-B (unsurprising). I live in a Mode C veil, so a transponder (and, in a year ADS-B) will be required. I have an extensive electronics background, but I have not worked on airplanes.

    As I evaluate airplanes, I would like to know what I need to do to install a Transponder in an experimental. I am not too worried about installing ABS-B on something with a transponder (because of the uAvionics Skybecon), but I cannot find information on installing a transponder from scratch. Does anyone know a link to instructions or an install video to install a transponder/encoder on a plane that has not had one before?

  2. #2
    CarlOrton's Avatar
    Join Date
    Jul 2011
    Location
    DFW Area
    Posts
    608
    Hi, This;

    While I don't have either a link to, or the actual instructions, I installed my own transponder in my homebuilt in 2012. It was a microair 2.25" unit. I thought it was simple and straightforward.

    Just connected a data cable from my EFIS to the transponder so the altitude could be provided (along with power) and then antenna cable to a standard rod antenna on the belly.

    Since I'm also under a Mode C veil, I had the local instrument shop guy come to the hangar to do the biennial transponder cert to ensure what the pitot was sensing was what the transponder was reporting.

    I'll install my own on my current build project as well, albeit with ADS-B out, which requires just a bit more stuff like having a WAAS GPS source. Still haven't decided which solution to use in this instance. Still waiting for the $1000 ADS-B transponder in a box solution. ;-)

    Carl Orton
    Sonex #1170 / Zenith 750 Cruzer
    http://mykitlog.com/corton

  3. #3

    Join Date
    Jul 2011
    Location
    Clarklake, MI
    Posts
    2,354
    Intstall transponder. Install antenna. Install an altitude encoder (usually a blind encoder). Connect the wires then spend some quality time with an avionics shop for an Appendix E/F check

  4. #4
    cub builder's Avatar
    Join Date
    Nov 2011
    Location
    North Central AR
    Posts
    420
    I recently replaced the old Terra Transponder in one of my planes with a Sandia Aerospace STX-165. It has the encoder integral to the transponder, so you install power, ground, antenna, and connect a hose to the static port. That's it, unless you add in the overpriced OAT probe. Fits either a 3-1/8 round instrument hole, or can be adapted to fit half width in a standard transponder mounting hole, or custom cut your panel to fit.

    After installation, you need to swing by a radio shop to have the transponder tested for output, frequency and correct altitude reporting. (regular transponder cert).

    The STX165 does give you the option of running a cable to your EFIS to supply it with pressure altitude, or to plug into separate encoder if you want (EFIS Supplying pressure Altitude).

    -Cub Builder
    Last edited by cub builder; 11-05-2018 at 03:46 PM.

  5. #5

    Join Date
    Feb 2012
    Location
    Barrington, IL
    Posts
    115
    Quote Originally Posted by thisadviceisworthles View Post
    I. Does anyone know a link to instructions or an install video to install a transponder/encoder on a plane that has not had one before?

    AC 43.13-2B - Acceptable Methods, Techniques, and Practices - Aircraft Alterations


  6. #6

    Join Date
    Dec 2018
    Posts
    2
    Probably not a lot of discussion because it's stone simple. Hookup power, ground and maybe a wire to the dimmer bus. Connect the antenna and you're done. It's a radio, but there's no audio in/out, so way simpler than a comm. The altitude encoder is nine wires (usually labeled A1, A2, A4, B1, B2, B4, C1, C2, C4) that go from the encoder straight to the corresponding terminals on the transponder. Here's a typical schematic:

    Name:  txp.jpg
Views: 294
Size:  39.1 KB

  7. #7
    Sam Buchanan's Avatar
    Join Date
    Nov 2011
    Location
    KDCU
    Posts
    451
    Quote Originally Posted by camorton View Post
    Probably not a lot of discussion because it's stone simple. Hookup power, ground and maybe a wire to the dimmer bus. Connect the antenna and you're done. It's a radio, but there's no audio in/out, so way simpler than a comm. The altitude encoder is nine wires (usually labeled A1, A2, A4, B1, B2, B4, C1, C2, C4) that go from the encoder straight to the corresponding terminals on the transponder. Here's a typical schematic:
    The newer digital transponders and encoders are even easier to hook up than that.......only one serial data wire needed to connect the altitude encoder to the transponder instead of all those gray code connections. Gray code equipment still works but is now very old school.
    Sam Buchanan
    The RV Journal RV-6 build log
    Fokker D.VII semi-replica build log
    YouTube Channel

  8. #8

    Join Date
    Jun 2018
    Location
    ATL
    Posts
    49
    Thanks for all of the information. It's good to know that a lack of a transponder is not a dealbreaker. Now I just need to find something with the useable load I want, that is in my price range.

  9. #9

    Join Date
    Dec 2018
    Posts
    2
    Well the good news is now lots of people are installing ADS-B, so there's a huge glut of older (but still functional) mode A/C transponders on the market. The economics of installing one are questionable since you'll still need to add ADS-B out by 2020, but it's an option if you're on a super tight budget. Cheaper UATs may still hit the market.

    C.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •