GMA 340 Audio Panel pilot’s guide 1
Front Panel Controls (GMA 340) Front Panel Controls (GMA 340 Dual ADF) Front Panel Controls (GMA 340H) 2
Function Selection Switches The left small knob (5, 7) on all units controls ON/OFF function. MKR BCN 1. 2. 3. 4. Marker Beacon Lamps Marker Beacon Receiver Audio Select/Mute Button Marker Beacon Receiver Sensitivity Indicator LED’s Marker Beacon Receiver Sensitivity Selection Button ICS 5. 6. 7. 8. 9. 10.
On, Off, and Failsafe Operation The GMA 340 is powered off when the left small knob (5, 7) is rotated fully CCW into the detent. To turn the unit on rotate the knob clockwise past the click. The left small knobs also functions as the pilot or copilot’s ICS volume control on the appropriate unit. A failsafe circuit connects the pilot’s headset and microphone directly to COM 1 in case the power is interrupted or the unit is turned off.
Com Swap Function The GMA 340 allows the use of a remote mounted switch (typically on the yoke) to alternately transfer the active microphone back and forth between COM 1 and COM 2. Pressing the remote switch will have no affect if COM 3 is the active transceiver. Ask your installing agency for details. Aircraft Radios & Navigation F Audio level is controlled by the selected NAV radio volume control.
Intercom System (ICS) (Pilot and Copilot functions are reversed on the 340H) Intercom volume and squelch (VOX) are adjusted using the following front panel knobs: • LEFT SMALL KNOB — Unit ON/OFF power control and Pilot ICS volume. Full CCW DETENT position is OFF. • LEFT LARGE KNOB — Pilot ICS mic VOX squelch level. CW rotation increases the amount of mic audio (VOX level) required to break squelch. Full CCW is the “hot mic” position. • RIGHT SMALL KNOB — IN position: Copilot ICS volume.
• PILOT mode isolates the pilot from everyone else and dedicates the aircraft radios to the pilot exclusively. The copilot and passengers share communication between themselves but cannot communicate with the pilot or hear the aircraft radios. • CREW mode places the pilot and copilot on a common ICS communication channel. The passengers are on their own intercom channel and can communicate with each other, but cannot communicate with the crew or hear the aircraft radios.
Marker Beacon Receiver The marker beacon is used as part of an ILS approach, and in certain instances, to identify an airway. In addition to the normal marker beacon functions, the GMA 340 provides an audio muting function. The lamps illuminate, and an associated keyed-tone is heard when MKR audio is selected, when the aircraft passes over a 75 MHz marker beacon transmitter.
Limited Warranty GARMIN Corporation warrants this product to be free from defects in materials and workmanship for one year from the date of purchase. GARMIN will, at its sole option, repair or replace any components which fail in normal use. Such repairs or replacement will be made at no charge to the customer for parts or labor. The customer is, however, responsible for any transportation costs. This warranty does not cover failures due to abuse, misuse, accident or unauthorized alteration or repairs.
GMA 340 GMA 340 Dual ADF GMA 340H 11
© 2001 GARMIN Corporation GARMIN International, Inc. 1200 East 151st Street, Olathe, Kansas 66062, U.S.A. GARMIN (Europe) Ltd. Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9AQ, U.K. GARMIN Corporation No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan www.garmin.com Part Number 190-00149-10 Rev.
