Rohde & Schwarz R&S SMU200A, Service Manual

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R&S SMU200A Test Procedures
1007.9845.82 1.39
E-12
Phase Modulation (Option R&S B20/B22)
PhiM Setting Uncertainty
Test Method
Spectrum Measurement (see chapter " Test Methodes ").
Measurement
Settings on DUT:
RF On
Level 0 dBm:
Phase Modulation menu:
Source Internal
State on
Settings on spectrum analyzer:
see chapter "
Test Methodes "
Recommended settings
CF sweep
10 MHz, 250 MHz, 500 MHz, 812 MHz, 940 MHz, 1067 MHz,
1194 MHz, 1321 MHz, 1484 MHz, 2200 MHz, 4000 MHz, 6000 MHz
with fmod = 10 kHz, deviation = 1 rad.
Deviation sweep
Measurement at CF 500 MHz, f
mod
= 10 kHz,
deviation 1 mrad to 2.5 rad in logarithmic steps,
4 steps per decade (1, 1.8, 3.2, 5.6)
Repeat measurement at 500 MHz with external modulation.
PhiM Distortion
Test Method
FFT Demodulation (see chapter "
Test Methodes
")
Measurement
Settings on DUT:
RF On
Level 0 dBm
Frequency Modulation menu:
LF Gen Frequency 10 kHz
Source Internal
PhiM deviation 1 rad.
Settings on R&S FSQ:
see chapter "
Test Methodes
"
SWEEP / MEAS TIME 2.5 ms,
FREQ / AF STOP 50 kHz,
AMPTD / REF LEVEL 0 dBm,
FREQ / CENTER test frequency.
Read THD from the Display. To convert to percent calculate THDpct
= 100 * 10 ^(THDdB/20).
Recommended settings
CF sweep
10 MHz, 250 MHz, 500 MHz, 812 MHz, 940 MHz,
1067 MHz, 1194 MHz, 1321 MHz, 1484 MHz, 2200 MHz,
4000 MHz, 6000 MHz.