Comtech EF Data XPA-200 - Manual (Page 81)

XPA200-7984-I-OPT1, X-Band SSPA Addendum
SYMPTOM POSSIBLE CAUSES SOLUTIONS
XPA200-7984-I-0PT1, Rev.2 7.3
“AMPLIFIER = OFF” feature
activated.
Large customer attenuation
values selected.
Input power level not
correct, perhaps due to
faulty input cable.
Faulty input connection from
10V power supplies.
Faulty SSPA control cable or
connection.
Failed SSPA amplifier module.
allows for lower current draw
from the prime power source
under standby conditions. To
obtain RF output, ensure that
this feature is set to
“AMPLIFIER = ON”.
Check the “ATTENUATION = XX”
setting in the
“CONFIGURATION” menu. Lower
value to get more gain.
Use the input sample port on
the front panel to determine
that the input power level is
as expected.
Use the “MONITOR” menu to
check the internal level of
PS1 and PS2. The levels
should be near 10V. If not
correct, use a voltmeter to
measure the voltage where the
#8 wires enter the amplifier
unit. WITH UNIT OFF, tighten
connections if necessary.
Check the 25 pin ribbon cable
connections at the amplifier
module and at AS/0200.
This can usually be
determined by using the
“MONITOR” menu to check the
DC current levels being drawn
by each transistor inside the
amplifier module.
Any transistor (QX) current
that is 50 percent more or
less than nominal would
probably indicate a failure.
Nominal values:
Q1=20mA, Q2,Q3=1.5A,Q4=2A,
Q5=4A, Q6-Q11=7.5A, Q12-
Q19=9A.
There are no user serviceable
parts inside the amplifier
module. Return to factory
for repair.
No remote control
communication.
Incorrect cable connections.
Improper communication
Make sure cable is wired as
described in Section 5.
Check settings of SSPA along