Concepts and Features
R&S
®
ZNB/ZNBT
223
User Manual 1173.9163.02 ─ 38
of the R&S
ZNB/ZNBT, e.g. in the in the port configuration and in the power calibration
dialogs.
Zeroing
Zeroing calibrates the external power meter by adjusting its reading at zero signal
power. For this purpose, the RF cable between the analyzer and the power sensor
must be disconnected (see tips below!). R&S power sensors and power meters auto-
matically 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 power
meter model; refer to the documentation of your external power meter for more infor-
mation.
Repeat zeroing
●
During warm-up after switching on or connecting the instrument
●
After a substantial change of the ambient temperature
●
After fastening the power meter 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.
A reset of the network analyzer does not affect the last zeroing result.
4.7.19 External Generators
The connection of an external generator to the R&S
ZNB/ZNBT can serve different
purposes.
●
Extended measurement functionality: Each external generator represents an addi-
tional source port. External generators increase the number of RF input signals for
the DUT. A typical example is a mixer measurement with a 2-port analyzer, where
an external generator provides the LO input signal.
Optional Extensions and Accessories
