Garmin GTX 23 Manuale Utente

190-00906-01

GTX 23 Installation Manual

Rev. C

Page 2-5

After the cable assemblies are made and wiring installed to the rack back plate, route wiring bundle as 
appropriate.  Use cable ties to secure the cable assemblies and coax to provide strain relief for the cable 
assemblies.  When routing cables, observe the following precautions:

•

All cable routing should be kept as short and as direct as practical.

•

Avoid sharp bends to prevent insulation from being breached.

•

Avoid routing close to sharp edges to prevent insulation from being breached due to vibration or 
handling the cable.

•

Avoid routing cables near power sources (e.g., 400 Hz generators, trim motors, etc.) or near power 
for fluorescent lighting.

•

Avoid routing antenna cables near DME, TCAS, radar altimeter, and ADF antenna cables (allow at 
least a 12-inch separation).

Cooling air is generally not required.  However, if the unit is located in a confined space or near a source of 
heat, cooling air is recommended for maximizing the life of the GTX 23.  A 5/8 inch air fitting is provided 
on the rear of the backplate for the purpose of admitting cooling air.  If a form of forced air cooling is 
installed, make certain that rainwater or condensation cannot enter and be sprayed on the equipment. 

The GTX 23 mounting surface must be capable of providing structural support and electrical bond to the 
aircraft to minimize radiated EMI and provide protection from High-Intensity Radiation Fields (HIRF).  
The GTX 23 can be mounted using either a modular rack or a stand-alone rack. Ensure that the GTX 23 
chassis has a ground path to the airframe by having at least one rack mounting screw in contact with the 
airframe.

The racks can be installed in a variety of locations, such as the electronics bay, under a seat or on an 
avionics shelf behind the rear baggage area. Refer to Figure 2-4 for suggested locations. The racks should 
be mounted to a surface known to have sufficient structural integrity to withstand additional inertia forces 
imposed by the GTX 23 unit, rack, and connectors (see Section 1.7.1 for weight information). If it is 
necessary to build a shelf or bracket to mount the GTX 23 racks, or it is not certain that the chosen location 
is of sufficient structural integrity, refer to Appendix A for validation of rack mounting structures and 
determining static load capability. Leave sufficient clearance between the GTX 23 and any obstruction. 
Consider installing the rack in accordance with AC 43.13-2B Chapter 2 “Communication, Navigation, and 
Emergency Locator Transmitter System Installations”.

2.6.1 Stand-alone Rack Considerations
Figures 2-2, D-1, and D-2 show the GTX 23 remote-mounted stand-alone rack. Figure D-1 gives the stand-
alone rack dimensions for the GTX 23. The rack can be mounted vertically using four 8-32 pan head 
screws (MS35206, AN526 or other approved fastener). It can also be mounted horizontally using four 6-32 
100° counter-sunk flathead screws (MS24693, AN507R or other approved fastener). If more water-
resistance is desired, the rack should be installed in the upright vertical orientation only, otherwise, the rack 
may be mounted in either vertical or horizontal orientation.

2.6.2 Modular Rack Considerations
Figures 2-3, D-3, and D-4 show the GTX 23 remote-mounted modular rack. Figure D-3 gives the modular 
rack dimensions for the GTX 23. The modular rack can be mounted in any orientation and must be secured 
to the airframe using a minimum of eight 6-32 100° counter-sunk flathead screws (MS24693, AN507R or 
other approved fastener), two per position as indicated in Figure D-4.