Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
167 Operating Manual 1407.6062.32 ─ 08
It is possible to switch the permanent display active for several sensors. The instrument
indicates the values of a maximum of two sensors simultaneously, in ascending order of
connected channels. If you activate the display of a third sensor, the instrument fades
out the values of the last highest channel number automatically.
SCPI command:
​
SENSe<ch>[:
​
POWer]:
​
DISPlay:
​
PERManent:
​
STATe
​
on page 487
Display Priority - Power Sensors
Selects whether the average or the peak power measurement result is indicated when
permanent display is active.
SCPI command:
​
SENSe<ch>[:
​
POWer]:
​
DISPlay:
​
PERManent:
​
PRIority
​
on page 487
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
Source - Power Sensors
Selects the source for measurement.
"RF" Measurement source is the RF signal of the generator. The RF fre-
quency is used as the measurement frequency of the sensor and the
corresponding correction factor is used.
In this mode the RF frequency of the generator is send to the sensor
automatically if changed.
RF Signal and Analog Modulations - RF Block