R&S SM300, Руководство по обслуживанию

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R&S SM300 Manual Test Procedure
Version 04 77
Service Manual SM300: 1147.1652.00 Instrument Part No SM300: 1147.1498.03
Measurement 1. Settings on SM300
Test level 0 dBm, test frequency 850 MHz
Select Modulation I/Q
2. Settings on signal generator
Voltage 0.5 V (Vpeak) corresponding to 4 dBm.
3. Settings on analyzer
Center frequency = test frequency, Span 30 kHz, RBW 10 kHz,
Reference level = test level + 6 dB Scale 2 dB/div.
4. Vary the frequency from 9 kHz to 40 MHz on the signal generator and
measure the modulation sidebands on the analyzer (CENTER FREQ. =
test fre modulation frequency).
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The resulting level of a sideband frequency is the average value of the
left and the right sideband level.
5. For evaluation, determine the difference between the highest and the
lowest sideband.
The modulation frequency response is the difference between the highest
and the lowest sideband.
2.4.6 Pulse Modulation
Test setup Test setup 1 with spectrum analyzer
Settings on SM300
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LEVEL 10 dBm
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FREQ 1 GHz
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MODULATION PULSE On time 100 ms, Off time 100 ms
Setting on spectrum
analyzer
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Center 1 GHz
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Zero Span
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Reference level 10 dBm
Measurement 1. Note down ON time on spectrum analyzer
2. Note down OFF time on spectrum analyzer
2.4.7 Internal Modulation Generator
Note
The setting time is a pure computing time and does not have to be measured.
2.4.7.1 Level Accuracy
Test equipment AC voltmeter (Table Measuring equipment and accessories, item 12)
Test setup Connect AC voltmeter to LF connector of SM300
Settings on SM300 LF OUTPUT
Test level: 10 mV, 100 mV, 2 V
Measurement Measure output level
2.4.7.2 Frequency Response
Test equipment AC voltmeter (Table measuring equipment and accessories, item 12)
Test setup Connect AC voltmeter to LF connector of SM300.