Garmin gnc 420a User Manual

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GNC 420/420A Quick Reference
KEYS AND KNOBS
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190-00140-21  Rev. F
Large left knob
Large right knob
Small left knob
Small right knob
NRST
OBS
MSG (message)
FPL (flight plan)
PROC (procedures)
COM Power/ Volume
COM Flip-flop
CLR (clear)
ENT (enter)
MENU
RNG (map range)
Direct-to
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Figure 1-1  Keys and Knobs
Left-hANd Keys ANd KNobs
The COM Power/Volume Knob controls unit power 
and communications radio volume.  Press momentarily to 
disable automatic squelch control.
The large left knob is used to tune the megahertz (MHz) 
value of the standby frequency for the COM transceiver.
The small left knob is used to tune the kilohertz (kHz) 
value of the standby frequency for the COM transceiver. 
The  COM  Flip-flop  Key  is  used  to  swap  the  active 
and standby COM frequencies.  Press and hold to select 
emergency channel (121.500 MHz).