Operating Manual R&S SMIQ - Volume 1 - Rohde & Schwarz

SMIQTest Procedures5.3.12.3 FM Frequency ResponseFM frequency response up to 100 kHzTest assemblySee section "Test Assemblies", standard test assembly for analogmodulations with audio analyzerMeasurement Settings on SMIQ:- Test frequencies 100, 750.1, 1099, 1101, 1499 MHz- Level 0 dBm- Select EXT1 in the menu ANALOG MOD/FM/FM1 SOURCE,deviation each: ¼ of the maximum deviation. Setting on audio analyzer:- Generator level 1 V (V peak ) Vary the generator frequency of the audio analyzer from 10 Hz to100 kHz to determine the modulation frequency response. The modulation frequency response is the difference between thegreatest and the smallest modulation depth. Repeat the measurement, applying the signal to socket EXT2 andwith the setting ANALOG MOD/FM/FM2 SOURCE EXT2, only withCF 100 MHz. Repeat the measurement with the internal modulation generatorand with the setting ANALOG MOD/FM/FM1 SOURCE INT, onlywith CF 100 MHz.Broadband FM frequency response up to 2 MHzTest assemblySee section "Test Assemblies", broadband FMMeasurement Settings on SMIQ:- Select EXT2 in the menu ANALOG MOD/FM/FM2 SOURCEand select deviation according to the table below.- Switch the voltmeter to DC measurement. Vary the frequency in 10 kHz steps on the SMIQ or the auxiliarygenerator until the voltmeter indicates 0 V. Switch the voltmeter to AC measurement and vary the frequency onthe sinewave generator from 10 kHz to maximum frequency. Measure the modulation frequency response with the AC voltmeter. The modulation frequency response is the difference between thegreatest and the smallest modulation depth measured. Repeat the measurement, applying the signal to socket EXT1 andwith the setting MODULATION/FM/FM1 SOURCE EXT1.Recommended settings:F (RF) 50 MHz 750.1 MHz 1099 MHz 1101 MHz 1500 MHz 2200 MHz 3300 MHz 4400 MHz 6400 MHzDeviation 500 kHz 250 kHz 250 kHz 250 kHz 250 kHz 500 kHz 500 kHz 1000 kHz 1000 kHzMixer no yes yes yes yes yes yes yes yesF (LO) - 800.1 MHz 1149 MHz 1151 MHz 1550 MHz 2250 MHz 3350 MHz 4450 MHz 6450 MHz1125.5555.03 5.35E-9