Embraer EMB145 Operation Manual page 2389

SELCAL SYSTEM
The Ground-to-Air Selective Calling (SELCAL) System operates in
conjunction with the communication radios. The SELCAL provides
continuous monitoring of a pre-set frequency, eliminating the need to
continuously monitor the communication frequencies by the flight crew.
The SELCAL permits ground stations, equipped with encoding
equipment, to call individual airplane by transmitting a coded signal.
This coded signal will activate only one SELCAL unit to respond to that
particular coded signal. In this case, a SELCAL voice message is
activated through the Aural Warning Unit. Once activated, the system
is reset for further monitoring by pressing the SELCAL Button, located
on the Main Panel, or actuating the PTT function (on Control Wheel or
glareshield panel).
NOTE: - For some airplanes the SELCAL enables only the VHF 2
operation or only the HF operation.
- SELCAL will recognize the coded signal from ground stations
only if the associated system (HF or VHF2) is powered on
and its frequency is adjusted to the ground station frequency.
REVISION 17
AIRPLANE
OPERATIONS
MANUAL
NAVIGATION AND
COMMUNICATION
Page
1
2-18-23
Code
01