Using a Single HSS Unit Chapter 9RADWIN 5000 HPMP User Manual Release 3.2.00 9-4Using a Single HSS UnitFigure 9-5: HSS Wiring schematicThe wiring, as shown in Figure 9-5 is self explanatory. The Sync signal path is less self-evi-dent. If we set ODU 1 (on SYNC 1) to HSS Master, then the Sync signal path is as shown inFigure 9-6. The signal travels from ODU 1 to SYNC 1, from SYNC 1 to SYNC 2, from SYNC 2to ODU 2 and back again. The back and forth paths repeat for the second to fourth ODU,from left to right. The signal exits the HSS unit at SYNC 5 and terminates in ODU 5.The choice of the ODU on SYNC 1 as HSS master is not mandatory, but is good practice. If forexample we were to use ODU 3 as HSS master, the Sync signal path would be ODU 3 to SYNC3, then left and right to SYNC 2 and SYNC 4. It would then propagate to ODUs 2 and 4, termi-nating at both ODUs 1 and 5.Figure 9-6: HSS sync signal path with ODU 1 as HSS MasterUsing More than One HSS UnitIn a large collocation site, several HSS units may be cascaded (daisy-chained) subject to thefollowing conditions:Condition 1: Cabling Sequence1. Up to nine ODUs may be connected to the first HSS unit using HSS ports SYNC 1, SYNC 2,SYNC 3,... up to SYNC 9 in order without leaving empty ports.
