Embraer EMB145 Operation Manual page 2324

NAVIGATION AND
COMMUNICATION
7 - HEADPHONE MASTER VOLUME CONTROL KNOB
Allows adjustment of headphone amplifier volume.
8 - INTERPHONE SELECTOR KNOB
When depressed, enables communications between captain,
copilot, observer, and ramp station via airplane interphone.
When rotated, provides interphone volume control.
NOTE: To enable the interphone function the respective control
wheel and observer communications switch must also be
set at the HOT position.
9 - MARKER BEACON SENSITIVITY/MUTE KNOB
The mute function is enabled by pressing the marker beacon
sensitivity/mute knob and it is used to temporarily silence the
marker beacon audio signal. The audio signal will be
automatically re-enabled according the following schedule:
If the mute function was selected when the marker beacon
audio level was above a certain threshold setting, the audio
will be re-enabled 5 seconds after the audio level descends
below that threshold setting.
If the mute function was selected when the marker beacon
audio level was below that threshold setting, the audio
signal will be mute during 20 seconds, and then it will be re-
enabled.
The marker beacon sensitivity/mute knob, when rotated, also
controls the sensitivity of the Marker Beacon receiver.
10 - MARKER BEACON VOLUME KNOB
When rotated, allows to control the marker beacon audio
volume.
NOTE: Does not allow volume settings below a certain level in
order to prevent the marker beacon audio from being
adjusted too low to be heard, that the marker signal could
be missed.
11 - SIDETONE KNOB
This knob selects the speaker ON (depressed) or OFF
(pressed). It must be pressed when the headphones are used.
The sidetone control is made by rotating the sidetone knob,
which prevents undesirable feedback of speaker sidetone
audio into the transmitting microphone.
12 - SPEAKER MASTER VOLUME CONTROL KNOB
When rotated, allows adjustment of speaker volume.
Page
2-18-15 4
AIRPLANE
OPERATIONS
MANUAL
Code
01 REVISION 36