Terra Universal TRT-250D Transponder

Terra's TRT-250D transponder takes the all solid-state design of the TRT-250, and adds a more readable display and a number of convenience features. Like the TRT-250, the TRT-250D does not use a cavity tube. As a result, reliability is improved, and no warm-up time is needed before operation. This unit is small, lightweight, and has low power drain. Other TRT-250D features include:

Planar gas discharge display
Simultaneous display of active and standby codes
Pushbutton code flip-flop
Single knob code selection
Pushbutton VFR code selection (1200)
Mode C compatibility
200 watts nominal power output
4096 discrete codes
System test capability
TSO'd