Transponder

Equipment

An aircraft radio that replies to radar interrogations with an identifying code (squawk) and, in Mode C/S, altitude. It makes the aircraft show up clearly on the controller’s screen.

Also known as

xpdrmode smode c

See also

Squawk Squawk codes 7500/7600/7700 Squawk 7000 Squawk 7600 Squawk 7700

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