Rohde & Schwarz SME02 - Carrier Frequency Deviation with FM; FM Stereo Modulation

SME Test Procedure
1038.6002.02 5.25 E-13
5.2.26 Carrier frequency Deviation with FM
Test equipment
Test system 5.1.1.1
Measurement À Settings at the SME
- 400 MHz
- Level 0 dBm
- Select LFGEN1 in the MODULATION/FM/FM1 SOURCE menu,
- Deviation 0 kHz.
À Setting at the modulation analyzer
- Counter function
À Observe change when switching on and off FM.
Frequency deviation when switching on FM..........................< 50 Hz
À Increase the deviation at the SME to 200 kHz.
Frequency deviation when switching on FM.....................< 2050 Hz.
5.2.27 FM Stereo Modulation
Test equipment Test system 5.1.1.1
Test setup Connect the stereo coder output of the modulation analyzer with
socket EXT1 of the SME.
Measurement À Settings at the SME
- Carrier frequencies 10.7 MHz and 85 MHz to 108 MHz
- Select EXT1, DC coupled, in the MODULATION/FM/FM1
SOURCE menu,
- Deviation 46 kHz.
À Setting at the stereo coder
- Set the level such that neither EXT1 HIGH nor EXT1 LOW is
indicated.
À Modulate both channels with 1 kHz, determine the distortion factor
of both channels using the distortion meter in the modulation
analyzer.
Distortion factor ......................................................................< 0.1%
À Switch over deviation measurement to relative measurement and
operate both channels without a signal.
À Measure the signal to noise ratio in both channels according to
CCIR.
The unweighted and weighted signal to noise ratio must be more
than 76 dB.
À Modulate only one channel with 1 kHz. Measure the crosstalk
modulation in the unmodulated channel.
It should be more than 50 dB under the reference value of the
wanted modulation.