Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
198 Operating Manual 1407.6062.32 ─ 08
"High Devia-
tion" The maximum range for PhiM deviation is available. Phase noise is
improved for low frequencies compared to the default mode. The range
for modulation frequency is limited (see data sheet).
This mode is recommended for low modulation frequencies and/or high
PhiM deviation.
"Low Phase" Phase modulation with phase noise and spurious characteristics close
to CW mode. The range for modulation bandwidth and PM deviation is
reduced (see data sheet).
SCPI command:
​
[:
​
SOURce<hw>]:
​
PM:
​
MODE
​
on page 672
PhiM Deviation
Sets the modulation depth in RAD or degrees.
The maximal deviation depends on the RF frequency set and the selected modulation
mode (see data sheet). It is possible to enter a deviation that is too high for a certain RF
frequency or to vary the RF frequency to a range in which the deviation can no longer be
set. In this case the maximally possible deviation is set and an error message is displayed.
SCPI command:
​
[:
​
SOURce<hw>]:
​
PM[:
​
DEViation]
​
on page 671
LF Gen Frequency
Sets the frequency of the LF generator.
This setting affects all analog modulations which use the LF generator as the internal
modulation source.
SCPI command:
​
[:
​
SOURce]:
​
LFOutput:
​
FREQuency
​
on page 648
LF Gen Shape
Selects the waveform shape of the LF signal.
SCPI command:
​
[:
​
SOURce]:
​
LFOutput<ch>:
​
SHAPe
​
on page 655
PhiM Sensitivity
(Source External only)
Displays the input sensitivity of the EXT MOD input in RAD/V.
The modulation depth entered under "PhiM Depth" is reached with 1 volt (=U
peak
) of the
input signal.
Note: The input voltage should not exceed 1.1 V
p
otherwise modulation distortions might
occur.
SCPI command:
​
[:
​
SOURce<hw>]:
​
PM:
​
SENSitivity
​
on page 673
Mod External Coupling
Selects the coupling mode (AC OR DC) for external feed.
RF Signal and Analog Modulations - RF Block