Comtech EF Data CPA - Manual (Page 134)

CPA C-Band Indoor Solid State Power Amplifier Revision 1
Appendix B MN/CPA-IN.IOM
B–12
B.4.1 Case Examples
Case 1. Backup

Online unit(s)
1. Ensure the Online Unit attenuation is set to a value in dB greater than or equal to (≥ ) the
difference in levels measured above.
2. With the Backup Unit forced to be the active unit, adjust the OFFSET value in the CONFIG:
Redundancy  SSPA#1 menu to approximately the difference measured previously. This
will be a negative (-) number.
3. Toggle between the Online and Backup units as being the active path by forcing and un-
forcing a backup through the Backup Unit’s CONFIG: Redundancy  SSPA#1 menu.
Ensure the output levels measured are equal. If necessary, re-adjust the Offset Value until
equal levels are measured. (Note that the Backup Unit’s total attenuation level as now
indicated in the CONFIG: Amp  Attenuation menu will be equal to the setting of the
Online Unit less the OFFSET value.)
For Example: Online Unit Output Level 47.00 dBm
Backup Unit Output Level 45.25 dBm
Backup Unit Offset Value 0.00 dBm
Online Attenuation Setting 3.00 dB (must be >1.75 dB)
AFTER TOGGLING AND ADJUSTING:
Backup Offset Value
-1.75 dB
New Equalized Output Level 47.0 dBm
Backup Attenuation Setting 1.25 dB (3+(-1.75) = 1.25)