5.2.3 Gain Equalization Of Redundant Units - Comtech EF Data KPA-020IN Installation And Operation Manual

Ku-Band Solid-State Power Amplifier
Redundant Configuration

5.2.3 Gain Equalization of Redundant Units

Typical procedures to equalize the gain between the Backup Unit and the Online Unit(s) via the
Gain Offset adjustment in the backup unit's CONFIGURATION Menu are as follows:
Note: Make sure all connections are made as outlined previously in Sections 2 and 4.)
Determine the relative gain of the Backup Unit vs the Online unit(s).
Make sure the Online Unit is "online" and transmitting. This can be verified through the
CONFIGURATION Menu, and the front panel LEDs.
Step
1
2
3
4
5
Case 1. Backup < Online unit(s).
1. Ensure the online unit attenuation is set to a value in dB greater than or equal (≥ )
2. With the backup unit forced to be the active unit, adjust the Offset Value in the
3. Toggle between the online and backup units as being the active path by forcing
Procedures
Apply an RF signal to the RF redundancy input isolator. Monitor the output
power level at the waveguide switch output. (Make sure not to apply too
large of an input signal which will saturate the amplifiers. Also be sure to
have a properly rated load to measure the output power.)
Adjust the input signal power level and attenuation of the Online Unit to
arrive at the desired output power level.
Record the output level of the Online Unit in dBm.
Force the backup unit to be the active path as outlined in the
CONFIGURATION Menu. Ensure the Offset Value at this point is 0.0 dBm.
Record the output level in dBm of the back-up unit.
If the output levels are equal, no more adjustment is necessary. Otherwise
proceed as follows.
to the difference in levels measured above.
CONFIGURATION Menu to approximately the difference measured above.
This will be a (-) negative number.
and un-forcing a back-up through the back-up unit CONFIGURATION Menu
settings. Ensure the output levels measured are equal. If necessary, re-adjust the
Offset Value until equal levels are measured. (Note that the back-up unit total
attenuation level as now indicated in the CONFIGURATION Menu will be
equal to the setting of the online unit less the Offset Value.)
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MN/KPA.IOM