Trig TT 21 Mode S Transponder

Trig TT 21 Mode S Transponder


Trig TT21 Mode S Transponder built into a steel box and with a battery life of 15 hours, this unit is bespoke designed purposely for ballooning purposes.

With an optionally available bespoke Cordura or Leather case, this unit is the perfect addition to a professional balloon.

Trig TT21 Transponder Product Description

The TT21 is a two part transponder with a compact control head; this includes an inbuilt altitude encoder – saving further space and expense. A separate hardware box can be installed anywhere in the airframe. The mounted control head is only 54mm (2 3/25”) deep and can be fitted in panel using a 57mm (2 ¼”) round hole or smaller compact mount – the unit ships with the necessary fittings for both install options. The TT21 unit is highly efficient, ideally suited for use via an auxiliary battery in either gliders, balloons or foot launched flight.

Trig’s TT21 has a 130 watts nominal power output, making it a class 2 transponder that meets  international standards for 1090ES ADS-B Out (TSO C166b). The TT21 is ideal for use in flight where a light weight Mode S solution is required and is suitable for both IFR and VFR use.

  • Comes with integrated altitude encoder
  • Certified for IFR / VFR flight
  • Certified class 2 transponder 130 watts nominal output
  • Manual dimming feature (adjustable backlight)
  • Low weight – 440g (0.8 lbs)
  • Low power consumption
  • 1090ES ADS-B Out capable
  • EASA ETSO and FAA TSO Certification – includes TSO C166b the latest ADS-B standard
  • Unbeatable value and quality – designed and manufactured in the U.K.
  • Two year worldwide warranty




Steel Box with either a Cordura or Leather case

Size: 230mm x 190mm x 65mm

Weight: 3.0 kgs excluding charger

Battery: 12 volt, 4.1 A/H NiMh

Operating Time: In excess of 15 hours from a fully charged battery

Extended Operation: The unit comes with a cable for external power supply and it will switch automatically from internal to external battery for long flights

Charger: Separate Ansmann Automatic ACS110 110-230v

Charge Time: 6 to 8 hours with a fully discharged battery. The charger will automatically switch to trickle charge mode when the batteries are fully charged

Antenna: Supplied with Flexible Stub Antenna as standard (see picture of Standard Delivery) – rod antenna available in lieu if  preferred (top left picture). In addition it is supplied with 3 m cable with connectors fitted and ground plane for remote mounting of the antenna.

Antenna Option: SP-1090-4 Folded Top Antenna

Leather case as Option: Exceptional quality; Hand made in England using heavy duty hide and fitted with heavy duty D rings for securing in the basket and with an adjustable carry strap

Cordura case as Option: Hand made in England per order using quality Cordura with your choice of colours. Pocket for antenna and side handles, it features foam padding throughout and D rings for securing in the basket and with an adjustable carry strap.

Price includes VAT and delivery in the UK.

Cases are ordered separately

£2,000 + VAT


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