User's Manual Part 2

BTS Redundancy/Alarm Testing – continued
DRAFT
SCt4812T CDMA BTS Optimization/ATP
Mar 2001
3-92
68P09253A61
CSM, GPS, & LFR/HSO
Redundancy/Alarm Tests
Follow the procedure in Table 3-50 to verify the manual redundancy of
the CSM, GPS, and LFR/HSO boards. Verification of alarms reported is
also covered.
DO NOT perform the procedure in Table 3-50, unless the
site is configured with a LORAN–C or HSO timebase as a
backup for the GPS.
IMPORTANT
*
Table 3-50: CSM, GPS, & LFR/HSO, Redundancy/Alarm Tests
Step Action
n WARNING
Any BBXs enabled will immediately key-up. Before enabling any BBX, always verify that the TX
output assigned to the BBX is terminated into a 50 W non-radiating RF load! Failure to do so could
result in serious personal injury and/or damage to the equipment.
1 Enable the primary, then the redundant BBXs assigned to ANT 1 by selecting the BBX and
Device>Key Xcvr.
2 Disconnect the GPS antenna cable, located on top of the BTS frame (see Figure 3-23).
This forces the LORAN–C LFR or HSO board timebase to become the CDMA timing source.
3 Observe a CDMA timing reference alarm and source change is reported by the alarm monitor.
4 Allow the LFR/HSO to become the active timing source.
 Verify the BBXs remain keyed and INS.
 Verify no other modules went OOS due to the transfer to LFR/HSO reference.
 Observe the PWR/ALM LEDs on the CSM 1 front panel are steady GREEN.
5 Reconnect the GPS antenna cable.
6 Allow the GPS to become the active timing source.
 Verify the BBXs remain keyed and INS.
 Verify no other modules went OOS due to the transfer back to the GPS reference.
 Observe the PWR/ALM LEDs on CSM 1 are steady GREEN.
7 Disable CSM 1 and enable CSM 2.
 Various CSM source and clock alarms are now reported and the site comes down.
 Alarms clear when the site comes back up.
. . . continued on next page
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