(1) Antenna elevation indication. This fault
The SYSTEM FAULT indicator (RSS and/or CSS) will
will be displayed whenever the antenna drops below a
A safety-related (SAFETY ALERT) display will
preset elevation angle. The audible alarm will sound and
generate an RSS system alarm only when the on-line
an RSS system fault will be displayed on the alarm
transmit system is affected.
monitor. The on-line power amplifier will be shut down
During the data mode of operation, the
and the associated power supply will display several
status faults. It is highly probable that this fault cycle will
operator will be alerted to a loss of data traffic or loss of
have been initiated by a scan fault failure in the antenna
a receive or transmit carrier. The audible alarm will
sound and RSS and CSS system faults will be displayed
(2) Waveguide interlock indication. This fault
on the alarm monitor. The receive modem in the
will be displayed if a transmit waveguide connection
affected traffic channel will indicate, as applicable, a
opens at the antenna, antenna entry panel, or the SHF
receiver out of lock condition and a loss of sync. If the
output port of either power amplifier (PA). An open
operator so desires, the receiving equipment may be
connection at the standby (off-line) PA will not affect the
loop tested to determine that the equipment is
functioning properly and that the fault is indeed external
three (on-line) locations will sound the audible alarm,
d. Similarly, on the CSS side, a loss of data traffic
display an RSS system fault, and shut down the on-line
from the modem or mux will generate a CSS system
display several status faults.
fault and sound the audible alarm.
b. Fault Switches.
e. A CSS temperature indication display will not
(1) On the alarm monitor, and located behind
generate a system fault alarm. The audible alarm will
the access cover, are 12 fault switches. Switches 1-5
sound. The CSS TEMP FAULT is illuminated when the
are associated with the CSS faults, switches 6 and 7 with
temperature in the CSS rack system is not in the +32F
RSS-CSS fault and switches 8-12 with RSS faults. The
to + 120F range required by several CSS equipments.
alarm monitor will recognize a fault signal (switches 8
and 9) from only the selected on-line transmit units. The
5-9. RSS System Troubleshooting Chart
fault alarm input from the off-line or standby unit will
automatically be inhibited and the associated fault switch
Figure FO-1 presents a flow-type procedure to aid in
need not be placed in the OVERRIDE position.
isolating a transmit or receive system fault to the unit
(2) The selected alarmed units on the RSS
level. Note that more than one unit-level fault may be
side (RSS group) and CSS side (CSS group) are listed in
displayed at any one time. When the audible alarm
The fault switches can
sounds, the technician observes the fault display. As
below in (3), (4) and (5).
close as possible, the actual display is matched to those
(3) When the terminal is not operating in a
in the troubleshooting chart to help locate the source of
multichannel mode, the fault switches associated with
the failure. A notation at the end of each display then
the unused channels is placed to the OVERRIDE
defines the corrective action to be taken.
position (the OVERRIDE indicator will be illuminated).
Any alarm input from the channels will be overridden and
CSS System Troubleshooting Chart
no system fault will be displayed.
refer to figure FO-2 to aid in isolating CSS system faults.
Table 5-3. Alarm Monitor Fault Switches
Using the Fault
AN/FCC-98 No. 1
a. Safety Related Faults. On the alarm monitor,
the SAFETY ALERT group displays two types of safety
elated faults as follows: antenna elevation and
waveguide interlock. The two faults will sound the
audible alarm. The following is a description of these
Power Amplifier 1
Power Amplifier 2
safety-related faults and their effect on system operation
(refer to para 5-17i for more detail on the two faults).