Garmin GTN 625 Flight Manual page 9

The GPS navigation functions and optional VHF communication and navigation
radio functions are operated by dedicated hard keys, a dual concentric rotary
knob, or the touchscreen.
Figure 1 - GTN 750 Control and Display Layout
Figure 2 - GTN 635/650 Control and Display Layout
190-01007-A2 Rev. 6 AFMS, Garmin GTN GPS/SBAS System
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