Rohde & Schwarz FSP3 - Checking RF Attenuator (with Option B25)

R&S FSP Performance Test
1164.4556.82 1.35 E-1
Checking RF Attenuator (with Option B25)
Test equipment:
- Signal generator (refer to "Measurement Equipment", item 3)
Frequency 128 MHz
Maximum level  10 dBm
- Step attenuator (refer to "Measurement Equipment", item 11)
Frequency 128 MHz
Attenuation 0 to 80 dB in 5 dB steps
Attenuation accuracy < 0.1 dB
1
)
1
) If a step attenuator with lower accuracy is used, correction
of the measured attenuation is recommended.
Test setup:
 Connect RF output of the signal generator to RF input of the step
attenuator.
 Connect RF output of the step attenuator to RF input of the
R&S FSP.
Signal generator settings:
- Frequency 128 MHz
- Level 10 dBm
Step attenuator settings:
Attenuation 70 dB
R&S FSP settings:
- [ PRESET ]
- [ FREQ : CENTER : 128 MHz ]
- [ SPAN : 500 Hz ]
- [ BW : RES BW MANUAL : 1 kHz ]
- [ TRACE : DETECTOR : RMS ]
- [ BW : VIDEO BW MANUAL : 100 Hz ]
- [ AMPT : RF ATTEN MANUAL : 10 dB ]
- [ AMPT : -35 dBm ]
Reference measurement:
 Set marker to peak of signal:
- [ MKR  : PEAK ]
 Set reference to peak of signal:
- [ MKR : REFERENCE FIXED ]
Measurement
Step attenuator settings:
Attenuation { 80 dB - a
FSP
}
Refer to table below for values of a
ATT
.
R&S FSP settings:
- [ AMPT : RF ATTEN MANUAL : {a
FSP
} ]
- [ AMPT : {-45 dBm + a
FSP
} dBm ]
- [ MKR  : PEAK ]
Refer to table below for values of a
FSP
, a
ATT
and reference level.
Evaluation:
The difference between the level of the input signal of the FSP and the
reference (at 10 dB RF-Attenuation) is displayed in the marker field by
the reading ´Delta [T1 FXD]´.
a
ATT
in dB
80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5
a
FSP
in dB
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75
Ref. level
in dBm
-45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30