Agilent Technologies 8935 Series, Руководство пользователя

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Chapter 8 187
Performance Tests
RF Generator Residual FM Performance Test 4
RF Generator Residual FM
Performance Test 4
The purpose of this test is to verify that the Test Set meets the
specification limits in PTR (Performance Test Record)
Table 9-4, “RF
Generator Residual FM Test 4 Record,” on page 240 . The residual FM
of the RF generator is measured directly by the measuring receiver. An
external LO is used to improve the residual FM of the measuring
receiver. An audio analyzer with a CCITT psophometric filter is
required to measure the demodulated FM.
NOTE
Two setups are shown below and on the following page. The first setup
is capable of measuring signals to 1 GHz. The second setup has a
microwave converter which covers the full measurement range of FM
signals to 2 GHz. The microwave converter’s LO must be a low residual
FM synthesizer.
Initial Setup
Figure 8-7 Setup for Measurements to 1 GHz
DUPLEX OUT
Signal Generator
Measuring Receiver
Audio Analyzer
INPUT
MODULATION OUTPUT
EXT LO
INPUT
RF OUTPUT
INPUT 50
Ω