16KEY L OCKPress and hold the key programmed as Key Lock for1 second to lock/ unlock the transceiver keys. The followingkeys/ functions can still be used when Key Lock is active:Autodial, Key Lock, Monitor, Monitor Momentary, PTT,Squelch Off, Squelch Off Momentary, and Volume.If the key is programmed as Key Lock with Backup, whenthe transceiver power is turned OFF and then ON again, thekeys remain locked. Otherwise, when the transceiver poweris turned OFF and then ON again, the Key Lock function willbe cancelled.MONITOR/ S QUELCH O FFYou can use the key programmed as Monitor or Squelch Offto listen to weak signals that you cannot hear during normaloperation, to deactivate channel signalling, and to adjust thevolume when no signals are present on your selectedchannel.• Squelch Off: Momentarily press to hear backgroundnoise. Press the key again to return to normal operation.• Squelch Off Momentary: Press and hold to hearbackground noise. Release the key to return to normaloperation.• Monitor: Momentarily press to deactivate QT, DQT,DTMF, or FleetSync signalling. Press the key again toreturn to normal operation.• Monitor Momentary: Press and hold to deactivate QT,DQT, DTMF, or FleetSync signalling. Release the key toreturn to normal operation.