Rohde & Schwarz R&S FSH - Page 30

Performance Test R&S FSH
1145.5973.82 1.6 E-11
Checking the accuracy of the IF gain setting
Test principle: The IF gain of the R&S FSH can be switched from 0 to 15 dB by changing
the reference level.
Test equipment: - Signal generator (refer to section "Measurement Equipment and
Accessories", item 3)
Frequency 100 MHz
Maximum level  -10 dBm
Test setup:  Connect the RF output of the signal generator to the input of the
divider.
 Connect output 1 of the divider to the power sensor / power meter.
 Connect output 2 of the divider to the RF input of the SA.
Signal generator settings: - Frequency 100 MHz
- Level -4 dBm
 Determine the output power of the signal generator with the power
meter. Adjust the output power of the generator until the power meter
shows -10 dBm ± 0.2 dB.
R&S FSH settings:
- [ PRESET ]
- [ FREQ: 100 MHz ]
- [ SPAN : 10 kHz ]
- [ BW : MANUAL RES BW: 1 kHz ]
- [ BW : MANUAL VIDEO BW : 100 Hz ]
- [ TRACE : DETECTOR : RMS ]
- [ AMPT : Ref_Lev *)]
*) Refer to table under “Performance Test Report” for values of {Ref_Lev}.
Reference measurement:
 Set the marker to the peak of the signal.
- [ MARKER: SET MARKER: PEAK ]
The signal level L is displayed by the level reading of the marker.
Ref
-10dBm
= L - L
powermeter
Measurement
Signal generator settings: - Frequency 100 MHz
- Level Ref_Lev + 6 dB
 Determine the output power of the signal generator with the power
meter. Adjust the output power of the generator until the power meter
shows the value Ref_Lev ± 0.2 dB.
R&S FSH settings:
- [ AMPT : {Ref_Lev} ]
*) Refer to table under “Performance Test Report” for values of Ref_Lev.
- [MARKER: SET MARKER: PEAK ]
Evaluation: The signal level L
is displayed by the level reading of the marker.
The difference between the level inaccuracy of the R&S FSH and Ref
-
10dBm
(at 0 dB IF gain) is the uncertainty of the IF gain:
IF-Gain
accuracy
= (L - L
powermeter
) - Ref
-10dBm