Comtech EF Data KPA - Manual (Page 94)

KPA Ku-Band Indoor Solid-State Power Amplifier Revision 1
Appendix B MN/KPA.IOM
B–8
B.4 Gain Equalization of Redundant Units
To equalize the gain between the Backup Unit and the Online Unit(s), Gain Offset adjustment is
accomplished via the Backup Unit.
IMPORTANT
Before continuing, make sure that:
a) All external interface connections have been completed as outlined in
Sect. B.3, and
b) The Online Unit is online and transmitting – this can be verified by
observing the Online Unit’s front panel LEDs, and through the pertinent
configuration menus.
To determine the relative gain of the Backup Unit versus the Online unit(s):
Step Procedure
1 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.)
2 Adjust the input signal power level and attenuation of the Online Unit to arrive at the
desired output power level.
3 Record the output level of the Online Unit in dBm.
4 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 Backup Unit.
5 If the output levels are equal, no more adjustment is necessary. Otherwise proceed
as follows.
Section Notes: