Trig makes the world’s smallest and lightest Mode S certified GA transponders. The TT21 Trig compact transponder can fit into to the tightest panel space. This allows general aviation, light sport and glider pilots to fit other instrumentation or displays that otherwise might not have been possible. The TT21 is a class 2 transponder and our most popular compact transponder model.
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov.
I bought the TT-21 over 12 years ago. It has been on the aircraft and flying for around 900 hrs. In all sorts of environments, rain sleet sun night you name it. I can strongly attest to the units reliability and service. Not a single problem ever and for a mode S transponder that to this day I am not sure what it does differently than a plain mode C,,,,,. It worked perfectly. It was easy to install I did it myself as an A&P, cant be any simpler. I have yet to install the ADSB add-on but that is next. You want a great reliable transponder this is the one you ought to buy.
Please note, Aircraft Spruce's personnel are not certified aircraft mechanics and can only provide general support and ideas, which should not be relied upon or implemented in lieu of consulting an A&P or other qualified technician. Aircraft Spruce assumes no responsibility or liability for any issue or problem which may arise from any repair, modification or other work done from this knowledge base. Any product eligibility information provided here is based on general application guides and we recommend always referring to your specific aircraft parts manual, the parts manufacturer or consulting with a qualified mechanic.
The TT21 & TT22 does not come with a wire harness. They do come with connector kit (wire not included) so you can wire them as all applications will vary giving the installer the ability to make the best fit in the aircraft.
The FAA’s 2020 mandate for ADS-B Out a certified Class 1 transponder is required. The Trig TT22 matches this requirement by being a higher powered Class 1 device. Keep in mind that your aircraft must have a Certified WAAS GPS receiver as the position source.
A portable WAAS GPS cannot legally supply WAAS data to any transponder to be ADS-B out compliant.
No, the Dynon antenna can only be used with a Dynon Skyview system and the Dynon mode s transponder to be ADS-B out.
The TT21 does not include an antenna. We recommend Rami part number AV-22 stub antenna for certified aircraft. For experimental, the TED antenna is available, see part number 11-17995.
The TT22 wilt meet the requirements for the ADS-B out only if wired to a GTN 650 or GTN 750 as well as a GNS 430W or 530W unit. Trig also makes a TN 70 which when wired will make the TT22 ADS-B out. The TT21 has a lower watt output and does not meet the 2020 ruling.
The TT21 kit includes the transponder, remote controller, mounting tray, installation manual, and connector kit.
This will include the transponder, the tray, connector kit and the control head.
Yes, this kit includes the control head, the transponder, the connector kit, and the tray.