User Manual

Loss/Gain Offset68P09255A57-2
Aug 2002
SC4812ET Optimization/ATP Manual Software Release R16.1.x.x
PRELIMINARY
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Table 3-33: Cable Calibration
Step Action
1 From the Util menu, select Cable Calibration. A Cable Calibration window is displayed.
2 Enter a channel number(s) in the Channels box. Multiple channels numbers must be separated with a
comma, no space (i.e., 200,800). When two or more channels numbers are entered, the cables will be
calibrated for each channel. Interpolation will be accomplished for other channels as required for TX
calibration.
3 Select TX and RX CABLE CAL, TX CABLE CAL or RX CABLE CAL in the Cable Calibration
picklist.
4 Click OK. Follow the directions displayed for each step. A status report window will be displayed
with the results of the cable calibration.
Calibrating TX Cables Using a Signal Generator and Spectrum Analyzer
Follow the procedure in Table 3-34 to calibrate the TX cables using the
signal generator and spectrum analyzer. Refer to Figure 3-21 for a
diagram of the signal generator and spectrum analyzer.
Table 3-34: Calibrating TX Cables Using Signal Generator and Spectrum Analyzer
Step Action
1 Connect a short test cable between the spectrum analyzer and the signal generator.
2 Set signal generator to 0 dBm at the customer frequency of 869-894 MHz for 800 MHz CDMA and
1930-1990 MHz band for North American PCS.
3 Use spectrum analyzer to measure signal generator output (see Figure 3-21, A) and record the value.
4 Connect the spectrum analyzers short cable to point B, as shown in the lower portion of the
diagram, to measure cable output at customer frequency (869-894 MHz for 800 MHz CDMA and
1930-1990 MHz for North American PCS) and record the value at point B.
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Calibration factor = A - B Example: Cal = -1 dBm - (-53.5 dBm) = 52.5 dB
NOTE
The short cable is used for calibration only. It is not part of the final test setup. After calibration is
completed, do not re-arrange any cables. Use the equipment setup, as is, to ensure test procedures use
the correct calibration factor.
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