Teledyne HPAC-2005, Руководство по эксплуатации

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3 RU SSPA Chassis Operations Manual 205356 REV T 67
3.0.7 Low RF Fault
In the case of a Low RF alarm, follow the steps below.
•
Check the forward RF level on the front panel readout under the system
information menu. If the user has access to a power meter or spectrum
analyzer, this power level can be verified by means of the output sample
port on the front panel.
•
Compare this value to the forward RF alarm threshold level in the Fault
Set-up menu. If the Threshold level is higher than the actual RF output
level, this will produce a low RF alarm, providing that the low RF alarm
option is enabled.
•
At this point, be sure that the forward RF alarm threshold level is set to a
value corresponding to the desired output level for the SSPA in question.
The factory pre-set for this value is always 10 dBm below the specified
P
1db
compression point of the SSPA. However, you may wish to set this
level closer to the desired output level in order to catch any minor fluctua-
tions below the set level. If the level is set too high, the low RF alarm may
be displayed when there are no legitimate problems. If the RF input sig-
nal has been lowered, this will also lower the output of the SSPA and
may cause a low RF alarm.
•
If the user is certain that the amplifier is in an alarmed state due to prob-
lems other than the ones stated above, the user should verify that no oth-
er fault conditions are present. If a power supply fault, current fault, or
voltage fault is present, this may also cause the low RF alarm to show. If
any of these is the case, the user should refer to the sections corre-
sponding to that specific fault.