Audio & Alerts · Menu 21
Squelch threshold — higher values require stronger signals to open the audio gate.
MENU on the radio to open the menu.21: Squelch.MENU again to enter the setting.MENU to save, or EXIT to cancel.RX Save— Battery-saver ratio — duty cycle of receiver active time vs sleep time in standbyVOX Switch— Voice-activated transmit — automatically keys PTT when microphone detects speechVOX Level— VOX sensitivity — how loud audio must be to trigger voice-activated TXVOX Delay— VOX hang time — how long TX stays active after voice drops, preventing rapid cyclingTX OVer Time— TX timeout timer — automatically ends transmission after this duration to prevent accidental long keydownsSee the full RT-900 menu reference for all menu items.