Nautel NX5 AM, Руководство по эксплуатации и техническому обслуживанию

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NX5 OPERATION & MAINTENANCE MANUAL OPERATING THE TRANSMITTER
PAGE 3.2.130 VERSION 0.1 2015-08-01
Exciter Clock Calibration
The
Exciter Clock Calibration
page (see Figure 3.2.111 ) allows you to calibrate the internal clock
reference to an external 10 MHz clock by clicking the
Calibrate
button. Both exciters are calibrated at
the same time. Note: typically, a value change is not required.
The exciter clock may also be synchronized to a reference source, either an external 10 MHz reference
connected to J1B of the control/interface PWB or a Nautel optional GPS sync PWB. The frequency and
phase option is applicable for combined systems only. The exciter reference will lock to the external
source frequency within 10 mHz (0.01 Hz) using the 10 MHz sync input, to within 2 mHz (0.002 Hz)
using the GPS sync PWB without an antenna, and to within the the quality of the GPS system when
using the GPS sync PWB with an antenna.
Figure 3.2.111: System Settings - Exciter Clock Calibration
Procedure to calibrate the exciter clock:
1. Select the
Exciter Clock Calibration
option from the left side of the
System Settings
page to
open a related window on the right side of the page.
2. Connect an external 10 MHz source to A4J1B, verify a value near 10 MHz displays in both
External
Clock Frequency
fields, and click
Calibrate.
Procedure to synchronize the exciter clock:
1. Select the
Exciter Clock Calibration
option from the left side of the
System Settings
page to
open a related window on the right side of the page.
2. Connect a source (10 MHz input or GPS sync).
3. Select
Frequency
in the
Sync Enable
drop-down menu.
4. Select the appropriate source (
10MHz Sync Input
or
GPS Sync Card
) in the
Sync Source
drop-
down menu.
Enable/Disable Frequency
If Disabled (default), no other
settings are required.
If Frequency, select Sync Source
(10MHz Sync Input or GPS Sync
Card). Selecting GPS Sync Card
also displays the Antenna Present
drop-down field (select Yes or No)
If Frequency and Phase (combined
systems only), enter Phase Offset.