Operating Instructions
Becker Avionics
Transmit Mode
18
VHF Transceiver 0638.420-071 Issue 06 02/2021
•
If PTT input is active (PTT=Push To Talk key is pushed) the
transceiver is set to transmit mode.
o
Microphone(s) signals can modulate the transmitter.
o
PTT 1 input starts transmission from microphone path 1.
o
PTT 2 input starts transmission from microphone path 2.
o
If "BOTH MIKES" are enabled in the configuration setup*,
each input (PTT 1 or 2) can start the transmission from
both microphone paths at the same time.
•
The "TX" symbol shows that the device is in transmit mode.
•
The sidetone (demodulated audio of the emitted signal) is
available on the headphone output.
•
The transmit mode automatically deactivates the speaker.
* For details please refer to related manual:
http://www.becker-avionics.com/manuals/
→
VHF Transceiver
•
In transmit mode some user actions are blocked e.g. change
the frequency selection mode or channel spacing mode, which
are normally permitted in receive mode.
•
Changes in standard mode e.g. the "Preset" frequency are
possible even during transmission.
•
In transmit mode is no intercom operation possible.
•
Transmit mode is automatically terminated (return to receive
mode) after 120 s of continuous transmitting.
o
The display shows "STUCK PTT", see "Warning and
Failure Indications", page 36.
o
For the start of a new transmission first it is necessary to
set the /PTT line inactive.
118.005
127.000
TX
