Remote Control - Commands
R&S NRP-Z27/-Z37
1169.3870.12 6.4
E-2
CALibration:ZERO:AUTO[?] OFF | ON | ONCE
The commands
CALibration:ZERO:AUTO ON
and
CALibration:ZERO:AUTO ONCE
perform zeroing.
For this purpose, the test signal must be deactivated or the power sensor module disconnected from
the signal source. The power sensor module automatically detects the presence of any significant
power to be measured. This causes zeroing to be aborted and error message
NRPERROR_CALZERO
to be output. The
CALibration:ZERO:AUTO OFF
is ignored. Zeroing takes four seconds at a minimum,
but at least as long as the selected averaging filter needs for settling (only fixed-filter mode).
Repeat zeroing
•
during warm-up after switching on or connecting the instrument
•
after a substantial variation 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.
For zeroing switch off the test signal and do not remove the power sensor module from
the signal source. Apart from keeping the thermal balance, this has the advantage that the
noise superimposed on the test signal (e.g. from a broadband amplifier) can be detected
on zeroing and does not impair the measurement result.
The query always yields
1
(=
OFF
).
Default setting
After a power-on reset, the zero offsets determined during the last calibration are used until the first
zeroing. Therefore, very slight zero offsets are to be expected with a warmed up power sensor module.
Initialization by means of
*RST
or
SYSTem:INITialize
has no influence on the current zero offsets.
