SeaSpace TeraScan 1.5M, Operation And Maintenance Manual

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SeaSpace Corporation
7.2.5 RF-Related Faults
7.2.5.1 L/S-Band Downconverter
7.2.6 Time-Related Faults
7.2.6.1 Check/reset clock
Use the date command to check system time and, if necessary, reset the system clock (section 10.3.5, page 186).
If the GPS antenna on your system is not operating, you can use the date command to reset system time before
attempting to correct the problem with the GPS.
7.2.6.2 Check GPS with sunclock and whereami
1. Enter (not as root user):
% sunclock
<Enter>
The error reported between the computer’s time and the GPS time should be less than one second.
2. Enter:
% whereami list
<Enter>
The current location should be reported.
CONDITION TEST CAUSE ACTION
Downconverter does
not switch frequency.
ac 1 O0000
(L-Band)
ac 1 O0001
(S-Band)
Observe signal input to
receiver using spectrum
analyzer. Watch a pass for
various satellites. Feed/LNA/
Downconverter is
defective. Replace {8.4.20}.
Power Injector
[12791001] is defective. Replace {8.4.21}.
RF coax cable [12574560]
is defective. Replace RF coax cable.