Kenwood TH78E - Manual (Page 54)

56
DUPLEX OPERATION
Normally this transceiver operats in a simplex mode,
i.e. No receive audio from the sub-band is fed to the
speaker during transmit on the main or active band.
If you prefer duplex operation, i.e. Receive audio
from sub-band is fed to the speaker during transmit
you must perform the following procedure.
Press and hold the F key for longer than one second
then press the DUAL key. The DUP indicator will
flash.
Press the F key then press the DUAL key. The DUP
indicator will appear on the display.
Duplex operation is now possible.
In this mode, the microphone sensitivity and receive
audio are reduced automatically to prevent howling.
The transmitter output power is also automatically set
to the EL position.
You can select the desired transmitter output power
by pressing the F key then the D/LOW key.
To cancel this function, repeat the procedure for
setting the function. The DUP indicator disappears
Occasionally the microphone might pick up receive
audio, causing howling to occur. To prevent howling
in the duplex mode, use an earphone (see page 50)
to listen to the receive audio, or perform the following
operation.
from the display.