Comtech EF Data KPA-020IN Installation And Operation Manual page 85

Ku-Band Solid-State Power Amplifier
Maintenance and Troubleshooting
No RF output or ≤ output
level.
Failed KPA amplifier
module.
No remote control
communication
Table 7-1. Troubleshooting (Continued)
Symptom Possible Cause
1. Mute fuction activated.
2. Amplification = Off
feature activated.
3. Large customer
attenuation values
selected.
4. Input power level not
correct.
5. Faulty input connections
from 9V supplies.
6. Fault KPA control cable
or connection.
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 transitor (QX) current
that is 50% more or less
than normal would
probably indicate a failure.
1. Incorrect cable
connections.
2. Improper
communication settings
between KPA and
controlling terminal.
3. Entry mode of unit set
to LOCAL.
1. Check the configuration menu to determine if
mute functions has been activated. Mute = On
Means that the unit is muted. Turn Mute
feature to Off to allow RF amplification of
the input signal.
2. The amplification = Off feature allows for
lower currect draw from the prome power
source under standby conditions. To obtain
RF output, ensure that this feature is set to
amplification = On.
3. Check the Attenuation = XX setting in the
configuration menu. Lower value to get more
gain.
4. Use the input sample port on the front panel
to determine that the input power level is as
specified. Remove and replace the input
cable.
5. Use the Monitor menu to check the internal
level of the PS1 and PS2. The levels should
be near 9V. 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.
6. Check the 25-pin ribbon cable connection at
the amplifier module and at AS/0200 PCB.
Tighten as necessary.
Nominal Values:
Q1 =
Q2 =
Q3, Q4 =
Q5, Q6, Q7 =
Q8 to Q19 =
Q20 to Q27 =
There are no user serviceable parts inside the
amplifier module. Return to factory for repair.
1. Ensure cable is connected properly.
2. Check settings of KPA along with remote
control terminal software.
3. Change entry mode setting in Configuration
menu to Remote.
7-4
Revision 0
MN/KPA.IOM
Solution
20mA
100 mA
1.0 A
2.0 A
2.25 A
5.5 A