Garmin MX20 Installation Manual page 53

10. From here you may follow the manufacturer's calibration instructions and procedure or set the roll/trim
parameter. Remember that the antenna is radiating during the setting of roll/trim.
11. To return to test mode and the test-pattern display, press the "MENU/ENTER" key. Once you return to
test mode, calibration mode is disabled.
12. So each time you return to test mode and the test pattern, and then return to the R/T Calibration SETUP
page (by pressing the "MENU/ENTER" key, you will need to press the "CALB" key again to enter
calibration mode.
2.9.9.3.3
Setting Roll/Trim
When setting roll trim, after returning to r/t calibration (setup) page, it is important to wait 30 seconds then
power-off. Do not attempt to re-enter calibration mode or use the unit without cycling the power.
2.9.9.4 Ground Based Checkout Procedures
2.9.9.4.1 Radar Test Mode Checkout
Turn power on to the MX20 I/O and radar antenna assembly. After the MX20 I/O self-tests are completed,
enter the Radar Function by pressing the FN key until the RADAR menu option is available. Then, press
the corresponding RADAR "smart key."
(If the Radar Function is not available, verify that the MX20 is an I/O model and that the radar function has
been enabled as described in previous sections).
The RADAR should remain in the off state with no scanning occurring when the Radar Function is entered
for the first time.
2.9.9.4.2 Test Pattern
Press the ON/STBY line item and allow approximately twenty seconds for the radar to power up. Verify at
this point that the RADAR powers up and performs the antenna clearance test. Once the unit is powered-
up, the radar will be in standby mode.
Press the TEST line item to place the unit in Test mode.
Verify that the test pattern is displayed. Press the range UP/DOWN keys if necessary until the test pattern
can be seen.
2.9.9.4.3 Tilt Test
Press the TILT line item and verify that the tilt can be adjusted from 15 UP to 15 DN: Pressing and holding
the key will auto increment the value.
Verify that both the RADAR antenna mechanically follows the commands and that the display tilt indicator
value on the MX20 I/O screen corresponds to the actual angle of the antenna.
2.9.9.4.4 Vertical Test - GWX 68 and ART 2000 ONLY
Press the VERT line item and verify that the antenna scan changes from the horizontal scan to the vertical scan.
MX20 Installation Manual 560-1025-09 Rev E
Installation
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