TT21 Mode S Transponder
The TT21 is a two part transponder system, which includes an integrated altitude encoder. In design and technology the TT21 is identical to the TT22; the only difference is that the transmitted output power of the TT21 is lower, qualifying the unit as a Class 2 transponder. Class 2 transponders may be used on aircraft cruising slower than 175 knots, and operating below 15,000 feet, IFR or VFR.
The front panel controller is smaller than a standard instrument, and the remote transponder is not much bigger than a pack of cards. The TT21 can fit into the smallest of aircraft – and yet it is fully certified and compliant with all the transponder requirements.
- Low Weight - less than 500 grams!
- Minimal Panel Space
- Low Power Consumption
- 130 Watts Nominal Output
- Integrated Altitude Encoder
- Simple Installation
- Support for 1090ES/ADS-B Out
The TT21 can be mounted in a standard 57 mm (2¼ inch) instrument hole, or where space is really tight, in a compact mounting just 42 mm high.
The TT21 is TSO approved for fitting to European and FAA registered aircraft.