Garmin 225B Manuale Utente

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Garmin GTR 225/225A/225B Pilot’s Guide

190-01182-00  Rev. A

The GTR 225 controls have been designed to simplify operation of the 

system and minimize workload and the time required to access sophisticated 
functionality. Controls are comprised of dual concentric knobs for frequency 
tuning, Com volume/squelch knob, and bezel keys. 

 The 

Power/Com Volume/Squelch knob located in the top left 

corner of the bezel controls audio volume for the Com radio. 
Rotating the knob clockwise past the detent turns power on 
and counter-clockwise turns power off. When the Com radio is 
active, press the Power/Com Volume/Squelch knob to toggle 
automatic squelch control On/Off for the Com radio. 

The Com radio features an automatic squelch to reject many localized noise 

sources. You may override the squelch function by pressing the Power/Com 
Volume/Squelch knob. This facilitates listening to a distant station or setting 
the desired volume level. 

To override the automatic squelch, press the Power/Com Volume/Squelch 

knob momentarily. Press the Power/Com  Volume/Squelch knob again to 
return to automatic squelch operation. A “SQ” indication appears to the left of 
the active Com frequency window in the upper left corner of the display when 
automatic squelch is overridden.