Garmin GTS 8 Series Installation Manual page 27

2.4.1.2 GTS 820 and GTS 850 Installations
GTS 820 and GTS 850 installation with both top and bottom mount directional antennas use one set of
coaxial cables for the four GTS 820 or GTS 850 TOP jacks (J1 TOP, J2 TOP, J3 TOP, J4 TOP) that are
connected to the corresponding GPA 65 processor unit jacks (J1U, J2U, J3U, J4U).
Each top cable assembly shall not exceed the maximum attenuation of 3.0dB at 1090MHz as shown in
Figure 2-4 and stated in Table 2-3. Each bottom cable assembly shall not exceed the maximum
attenuation of 2.5dB at 1090MHz as shown in Figure 2-4 and stated in Table 2-3.
A second set of coaxial cables are used to connect the four GPA 65 antenna jacks (J1A, J2A, J3A, J4A) to
the corresponding top antenna jacks (J1, J2, J3, J4). Each cable assembly shall not exceed the maximum
attenuation of 0.4dB at 1090MHz as shown in Figure 2-4 and stated in Table 2-3. A third set of coaxial
cables are used to connect the four LRU BTM jacks (J1 BTM, J2 BTM, J3 BTM, J4 BTM) to the
corresponding bottom antenna jacks (J1, J2, J3, J4). Each cable assembly shall not exceed the maximum
attenuation of 2.5dB at 1090MHz as shown in Figure 2-4.
Figure 2-4. GTS 820 and GTS 850 Installation with Top and Bottom Directional Antenna
If an optional bottom mount monopole antenna is installed, a single coaxial cable must be used to connect
the GTS 820 or GTS 850 J1 BTM jack to the monopole antenna jack. The cable assembly shall not
exceed the maximum attenuation of 2.5dB at 1090MHz as shown in Figure 2-5 and stated in Table 2-3.
Each of the remaining GTS 820 or GTS 850 bottom jacks (J2 BTM, J3 BTM, J4 BTM) are to be
terminated using a QMA 2 watt termination as specified in Table 2-2.
GTS 8XX/GPA 65 Installation Manual Page 2-9
190-00587-00 Revision 4TP