Harris DiamondCD Series, Техническое руководство

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5-30 888-2463-001 3/6/08
WARNING: Disconnect primary power prior to servicing.
Diamond Series™
Section 5 Maintenance and Alignments
STEP 3
When decreasing reject power for a module, reduce it a small amount,
then reduce the other in it’s pair a small amount and repeat until the pair
reaches a minimum. Also try to maintain a balance for groups of 4
modules (1-4, 5-8, 9-12 and 13-16). These tips should allow you to
reach a lower reject power percentage.
STEP 4
Carefully phase each high reading using the above techniques while
watching the Total Reject Power level and the individual module reject
level that was chosen for reduction. Sometimes increased phase (UP)
may be necessary; in other cases decreased phase shift (DOWN) might
be necessary. The goal is to reduce the total reject load power level to a
minimum amount. Levels of 3-4% or less should be achievable.
STEP 5
When the phasing adjustment is completed, the new settings must be
saved by pressing SAVE DATA and answering YES to the confirmation
query.
5.9 Cabinet Phase and Gain
Obviously, cabinet phase and gain is only for multiple cabinet transmitters. The Cabinet
Phase and Gain screen, shown in Figure 5-11, can be accessed directly from the Main
Menu or from the Module Phasing screen. The screen is monitoring the power levels
from each of the cabinet combiner reject loads.
The procedure is simple:
STEP 1
Select the cabinet to adjust by pressing one of the cabinet numbers 1, 2,
3, 4 or 5.
STEP 2
Adjust the Phase controls (Increase/Decrease) to reduce the power to the
combiner reject load for the cabinet selected in STEP 1. For coarse
phase adjustment press the Phase Adjust “SLOW” button to toggle it to
“FAST”. For fine phase adjustments, press it again to toggle it back to
SLOW.
STEP 3
If phasing alone will not sufficiently reduce the combiner reject power,
then the cabinet gain will have to be adjusted. This is done in the same
way. Select a cabinet to adjust and press Amplitude Adjust (Increase or
Decrease) to reduce the reject load power.
STEP 4
Reject load power should be below 4% on a properly adjusted system.
STEP 5
When Finished Press “Save Data”. To discard any changes made or simply
start over, press “Undo Changes”.