Comtech EF Data HPOD, Инструкция по установке и эксплуатации

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HPOD C-, X-, Ku-Band High-Power Outdoor Amplifier
Revision 9
Appendix B B–3 MN/HPOD.IOM
The system can be operated manually by sending an FBU=1 command (which forces SSPA 1 to
be backed up), or a FBU=2 command (which forces SSPA 2 to be backed up) to the BU.
In 1:2 applications, the BU also stores an offset value, to be used when the BU replaces an active
unit, for each of the two online units. This offset may be set with the SBO= command. When an
online unit is being “backed up” the BU’s attenuator will be set to this value. This value may be
different than the attenuation value of the online unit to compensate for any gain mismatch
between the BU and online units.
To calibrate, do these steps:
Step Task
1 After proper operating levels have been established in online SSPA 1 and 2, store their
attenuation settings using the SBO= command in the backup unit.
For example – SSPA 1, the active SSPA, requires 15.00 dB of attenuation. SSPA 2, the BU unit,
requires 10.00 dB: Enter the remote commands SBO=1,15.00 and SBO=2,10.00 to store these
values.
2 Send the FBU=1 command to the BU unit. This will force the BU unit to replace SSPA 1. The BU
unit will read the setting stored by the SBO=1 command (in this example, 15.00) and apply this
value to its own attenuation setting. This value can now be tuned to compensate for any gain
mismatch.
For example – If the output power is 1 dB too high in this state, send ATT=16.00 to the BU unit. If
the Tx level is now correct, send SBO=1,16.00 to the BU unit.
3 Repeat the above process to achieve desired level matching and for SSPA 2.