Kenwood TK-3101 Instruction Manual page 9

QT and DQT are functions that reject signals from
undesired persons that are using the same channel as
you. A QT tone or DQT code is programmed at the
factory in each of the channels. After selecting a
channel, you will hear audio from the speaker only when
you receive a signal that contains the matched code.
Likewise, when you transmit on a channel set up with
QT or DOT, the receiving station must have a matching
code in order to hear your signal.
You can change the codes programmed in the channels.
Select from among the 38 codes listed below. After
changing a code, confirm that other members in your
group have selected the same code.
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