User's Manual Part 2

Test Set Calibration – continued
DRAFT
SC4812ET BTS Optimization/ATP — CDMA LMF
Apr 2001
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Calibrating RX Cables Using a
Signal Generator and
Spectrum Analyzer
Follow the procedure in Table 3-27 to calibrate the RX cables using the
signal generator and spectrum analyzer. Refer to Figure 3-14, if required.
Table 3-27: Calibrating RX Cables Using a Signal Generator and Spectrum Analyzer
Step Action
1 Connect a short test cable to the spectrum analyzer and connect the other end to the Signal Generator.
2 Set signal generator to –10 dBm at the customer’s RX frequency of 1750–1780 MHz for Korean PCS
and 1850–1910 MHz band for North American PCS.
3 Use spectrum analyzer to measure signal generator output (see Figure 3-14, “A”) and record the value
for “A”.
4 Connect the test setup, as shown in the lower portion of the diagram, to measure the output at the
customer’s RX frequency in the 1850–1910 MHz band. Record the value at point ‘‘B”.
5 Calibration factor = A – B
Example: Cal = –12 dBm – (–14 dBm) = 2 dB
NOTE
The short test cable is used for test equipment setup calibration only. It is not be 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.
Figure 3-14: Calibrating Test Equipment Setup for RX ATP Test
(Using Signal Generator and Spectrum Analyzer)
Spectrum
Analyzer
Signal
Generator
A
B
Spectrum
Analyzer
SHORT
TEST
CABLE
SHORT TEST
CABLE
CONNECTION TO THE OUTPUT
PORT DURING RX MEASUREMENTS
Signal
Generator
BULLET
CONNECTOR
LONG
CABLE 2
CONNECTION TO THE RX PORTS
DURING RX MEASUREMENTS. FW00294
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