User's Manual Part 2

Test Set Calibration – continued

DRAFT

Mar 2001

3-59

SCt4812T CDMA BTS Optimization/ATP

Calibrating TX Cables Using a

Signal Generator and

Spectrum Analyzer

Follow the procedure in Table 3-27 to calibrate the TX cables using a

signal generator and spectrum analyzer. Refer to Figure 3-17 for a

diagram of the signal generator and spectrum analyzer.

Table 3-27: 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

– 1930–1990 MHz for North American PCS.

– 1840–1870 MHz for KoreaN PCS

3 Use a spectrum analyzer to measure signal generator output (see Figure 3-17, A) and record the

value.

4 Connect the spectrum analyzer’s short cable to point B, (as shown in the lower right portion of the

diagram) to measure cable output at customer frequency of:

– 869–894 MHz for 800 MHz CDMA

– 1930–1990 MHz for North American PCS.

– 1840–1870 MHz for Korean PCS

Record the value at point B.

5 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.