Garmin GDL 69/69A Installation Manual - page 27
Installation Procedure
GDL 69/69A Installation Manual
Page 2-11
190-00355-02
Revision E
bundle. Separation of the bundle into two smaller bundles, wrapped individually, may make
installation of the strain relief easier.
8.
Place the smooth side of the backshell strain relief (10) across the cable bundle and secure using
the three screws (11).
WARNING
Placing the strain relief grooved side across the cable bundle may cause damage
to wires.
9.
Attach the Spider terminal (2) to the backshell (1) by inserting the two screws (5) into the tapped
holes on the backshell (1).
10.
Attach a ring terminal (9) to the AWG #16 wire (3) length 24” and terminate to ground. The
ground connection can be made using either the closest aircraft ground or with tabs on racks.
Trimming of this wire to the shortest practical length before attaching the ring terminal is
recommended to reduce the effects of noise and interference. Do not extend this wire’s length.
2.5.6 Audio
Suppression
XM Audio Entertainment to crew locations may require audio suppression to comply with the STC
Limitations. Determine the activation state for each horn installed in the aircraft (aircraft power
signifying active high or ground signifying active low) by using one of the following methods:
• Find the horn and compare the installation with Figure D-5.
• Activate the horn per the method described in the aircraft’s maintenance manual. (For the gear
horn, this may require having the aircraft raised on jacks).
• With a multimeter, determine which horn contact changes state with the activation signal and if
the active state is high or low.
Wire the appropriate audio suppression input (high or low) in accordance with Figure D-5.
2.5.7 Remote Discrete Switches (Optional)
If XM audio entertainment is installed in the aircraft, optional functional switches may be installed as
desired. The functions of the switches must include the ability to mute the audio, adjust the volume and
channels. It may be incorporated as desired depending on the installation. Figure D-1 and Figure D-2
detail the wiring for the optional discrete switches. A common aircraft ground signal may be used for
each switch. It is recommended to use a rocker type switch for channel and volume control. Using a
rocker type switch will prevent inadvertently raising and lowering the channel at the same time as well as
the volume. An acceptable switch for this installation of the remote discrete switches is Carlingswitch
P/N 62111281-0-0-N (62111231-0-0-N for the switch used for muting). Since the input signals are
active-lo it is permissible to use multiple switches for each function. The would allow volume and
channel control to be available at each passenger station.