______________________________________________HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
58
STEP 2: Verify the RF level, 40 to 60mW.
STEP 3: Connect the 20 dB pad to the reflected input, connect the cable to the pad.
STEP 4:
Use the service screen to calibrate the reflected power metering to read
one percent of the forward power.
STEP 5: Remove the pad and reconnect the cable.
2.17.2.3 PA Cabinet Power Calibration
The sample elements have coupling ratios marked on the element. These can be used as
offset inputs to the power meter. The slave controller calibrate pot is adjusted for 3 volts
at the peak detector test point. Next use the PA service button to access and set the PA
power levels.
2.17.2.4 Two Cabinet Reject Load
The power in the reject load is half of a single cabinet with perfect hybrids. If the level
measured at the top of the control cabinet is in the 40 to 60 mW range, calibrate the
reject load to be 80 percent of the reject load rating.
2.17.2.5 Three and Four Cabinet Calibration
Using the tables below calibrate the reject loads. Data is in cabinet power percentages.
CABINET CABINET CABINET A/B AB/C COMBINED
A B C REJECT REJECT OUTPUT
100 0 0 50 16.6 33.3
0 100 0 50 16.6 33.3
0 0 100 0 66.6 33.3
100 100 0 0 66.6 133.3
100 0 100 50 16.6 133.3
100 100 100 0 0 300
Figure 2-1 Three Cabinets
CABINETS A/B CABINETS C/D AB/CD COMBINED
A & B REJECT C & D REJECT REJECT OUTPUT
ONE 50 BOTH 0 25 225
BOTH 0 ONE 50 25 225
BOTH 0 NONE 0 100 100
ONE 50 ONE 50 0 100
BOTH 0 BOTH 0 0 400
Figure 2-2 Four Cabinets
To Next Page
Loading...
