Busy Channel Lock; Key Beep - Oricom DTX4000 Operating Instructions Manual

Operations
To reset
Press and hold SCAN/RM button while turning the power on.
The display "AL-reset" or "User-reset" will indicate reset type.
The reset type can select in menu mode.
The user reset will not delete any stored memory channels.
Squelch Tail
Squelch Tail is the noise heard after the transmitting party release PTT
and is heard by the receiving party.
If Squelch tail in turned ON, on both radios this squelch noise will be
muted.

Busy channel Lock

If the channel is already in use, you can prevent the UHF CB radio from
transmitting. This is particularly important when using CTCSS/DCS.

Key Beep

The Beep tone emits a tone when you press any of the buttons on the
microphone (except PTT button).
Logo Display
The logo display function can control disable and enable.
The off means Logo skip and power ON.
24