______________________________________________
HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
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PA cabinet systems, begin with the (A / B) and (C / D) phase and gain modules, then
proceed to the top level ([A+B] / [C+D]) module.
STEP 7:
Adjust phase and gain module phase control for minimum reject power.
STEP 8:
Adjust gain control for minimum reject power.
STEP 9:
This completes the phase and gain module alignment in two PA system.
For larger systems, proceed to the next phase and gain module.
STEP 10:
Using an external power meter or calorimetric metering to confirm
power output, slowly increase power to 50%.
NOTE:
If external power meter and user display panel readings do not agree, refer to the
power calibration procedures in Section 2.16.
STEP 11:
Increase power slowly to 100%. In multiple PA systems, watch the reject
load power while increasing drive, and make slight readjustments to the phase and gain
module controls as above if necessary. Note that the second half of the green LED on each
visual PA module illuminates, indicating presence of RF drive.
STEP 12:
Compare DC INPUT POWER and 50 volt supply currents to factory test data.
STEP 13:
Check all PA modules for output one at a time by squeezing the disable
switch for each module and noting a drop in power output of the cabinet as seen on the PA
cabinet power information screen. Re-enable each module using a transmitter ON
command before proceeding to the next module. Wait 5 or 10 seconds for the re-enabling
of the module to take effect. Each module turn off should cause approximately the same
change in cabinet power output. Remember this requires AGC to be turned off.
STEP 14:
Switch AGC back ON when done and RAISE power to 100%.
NOTE:
Refer to AGC adjustments if needed.
2.16.2 Initial Application of RF Aural Power
STEP 1:
Check to insure the AGC module is OFF.
STEP 2:
LOWER the aural exciter drive to minimum.
STEP 3:
Press transmitter ON push-button.
STEP 4:
Check to see that all RF amplifier modules are enabled.