Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
171 Operating Manual 1407.6062.32 ─ 08
Note: In remote control, the sensors are set up using the
SENSe
commands. The remote
measurement is triggered by the
READ
query which also provides the measurement
results.
The software version of the connected power sensor can be retrieved by means of the
remote control command
:SENS:POW:TYPE?
.
Use the "Setup >"
​
chapter 5.2.3.6, "NRP-Z Info/Update" , on page 115 dialog to update
the sensor software.
SCPI command:
​
[:
​
SOURce<hw>]:
​
POWer:
​
SPC:
​
SELect
​
on page 682
State
Activates power control using the selected sensor.
The control loop periodically adjusts the generator output. After switching off, the running
loop is completed.
SCPI command:
​
[:
​
SOURce<hw>]:
​
POWer:
​
SPC:
​
STATe
​
on page 682
Measured Level
Indicates the current reading of the sensor.
Zero - Power Sensors
Activates the auto zero function.
Zeroing calibrates the external power sensor by adjusting its reading at zero signal power.
For this purpose, the RF power source must be switched off or disconnected from the
sensor (see tips below). R&S power sensors automatically detect the presence of any
significant input power. This aborts zeroing and generates an error message. Zeroing
can take a few seconds, depending on the sensor model; refer to the documentation of
your external power sensor for more information.
Tips for zeroing
Zeroing should be performed:
●
During warm-up after switching on or connecting the instrument
●
After a substantial change of the ambient temperature
●
After fastening the power sensor module to an RF connector at high temperature
●
After several hours of operation
●
When very low-power signals are to be measured, e.g. less than 10 dB above the
lower measurement limit.
●
Switch off the RF power source for zeroing; do not disconnect it from the power sen-
sor. In this way you will maintain the thermal equilibrium, and zeroing will also com-
pensate for the noise superimposed on the measured signal (e.g. from a broadband
amplifier).
SCPI command:
​
SENSe<ch>[:
​
POWer]:
​
ZERO
​
on page 492
RF Signal and Analog Modulations - RF Block