Retevis RT647 Mode D'emploi page 6

5. Busy channel lock
You can turn on/off this function via software.
A: If the current channel does not have CTCSS/DCS, When there is signal, TX prohibited
when you press PTT.
B: If the current channel does not have CTCSS/DCS, when there is signal which does not
have CTCSS/DCS, TX prohibited when you press PTT.
C: If the current channels does not have CTCSS/DCS, when there is signal which have
CTCSS/DCS, the radio will transmit when you press PTT.
6. TOT
The purpose of TOT is to prevent any radio from talking in one channel for a long time, and
to prevent the transceiver from being damaged because of continuous transmission. If the
transmitting time exceeds the TOT pre-set time, the radio will sound : Du, released PTT,
the radio will back received mode.
7. Voice prompt
The default setting is English voice prompt, and you will know the working condition of
the radio with voice prompt
1) The voice prompt can be selected "Chinese/English/Tone/OFF" through the menu
"Voice/Beep Tone" of the "Optional Features" in the software for. When choosing
"OFF", voice prompt turns off.
2) Channel annunciation: You will get to know the working conditions of current channel
which is being operated.
3) Low battery alert: The radio will alert you when the battery capacity reaches the
minimum operating voltage.
8. Squelch function
The squelch level will determine the signal strength to open the speaker of the radio. If the
squelch level is lower, the background noise of the opening the radios speaker will be
higher, and the corresponding communication range will be further, the the anti-interference
capacity will be weaker.
The default level if level 5, can set via the RT647 software, from 0-9.level0 is lowest
The level is higher, the squelch is more easy to be on.
9. CTCSS/DCS
CTCSS and DCS is the sub-audio signaling, to prevent the radio from receiving unwanted
signal in the same channel.
When the CTCSS/DCS is set, then within the communication range, you can only receive
signals from the same channel with the same CTCSS/DCS setting. When the CTCSS/DCS
is not set, you will get all the signal from the same channel within the communication range.
You can set the CTCSS/DCS through the menu "QT/DQT ENC" or "QT/DQT DEC" of the
"Channel information" in the software.