User Guide

Series III Avionics
Pilot's Guide
Page 30
DFS-43A Controls
Function Selector and Volume Control
OFF - Deactivates the DFS-43A System.
Records the last frequencies displayed in
the system's non-volatile memory.
ANT - Enables the DFS-43A System and the
non-directional sense antenna. The last
frequencies displayed reappear on the
display. Frequency tuning is enabled,
but no direction-finding capability exists
in this mode. External pointers park at
90°.
ADF - Standard direction finding mode. External
indicators point to station.
BRG - Digitally displays the magnetic bearing to
selected station. The FREQUENCY
TRANSFER pushbutton is disabled.
External equipment continues to function
in standard ADF mode.
NOTE:
BRG mode is not used for
navigation.
BFO - (Beat Frequency Oscillator) Identical to
ADF mode, but adds a 1,000-Hz tone to
audio.
Used only to identify interrupted-carrier
signals (also known as cw).