Pilot's Guide

190-01134-12 Rev. D Garmin GMA 350 Pilot’s Guide 11
GMA 350 Audio Panel
MARKER BEACON RECEIVER
The marker beacon receiver detects any marker beacon signal within
the reception range of the aircraft.
When a marker beacon signal is detected, the lamps illuminate, and
an associated keyed-tone is heard when MKR audio is selected. Marker
beacon lamps operate independently of any audio selection and cannot
be turned off.
Marker Beacon Key & Lamps
The marker beacon signal sensitivity threshold can be set to High, Low,
or User Selectable (toggle switch required).
The receiver detects the three marker tones (outer, middle, and inner).
Audio
Frequency
Audio Keying Lamp Actuated
400 Hz
(Outer)
− − − − −
Blue
1300 Hz
(Middle)
−−−−−
Amber
3000 Hz
(Inner)

White
The GMA 350 provides three states of marker beacon operation; On,
Muted, and Deselected. The MKR/MUTE key annunciator indicates
when marker beacon audio is selected. Marker beacon audio is not
heard when the annunciator is off or when the annunciator is on with the
marker beacon audio muted.