15 calibration subsystem – Boonton 4530 Peak Power Meter User Manual User Manual
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Chapter 4
Boonton Electronics
Remote Operation
4530 Series RF Power Meter
SENSe:CALTAB:INDEX
Description:
Set or return the array index for the first caltable element to be returned next time the
SENSe:CALTAB:DATA?
query is issued. Index 0 is the first element in the caltable, and
will contain the lowest power level in the sensor’s calibration. Index 4095 is the last element,
and contains the highest power level. Note that the table may be extrapolated, so it is
normal for the table extremes to be outside the power measurement range of the connected
sensor. Each time a block of data is read, INDEX is automatically incremented by the
COUNT value, so the full array can be split up into blocks of manageable size and read with
successive
SENSe:CALTAB:DATA?
queries. INDEX must be reset to zero for each new
caltable that is to be dumped, whether or not all the bins have been read.
Syntax:
SENSe:CALTAB:INDEX
Argument:
Valid Modes:
Statistical mode only.
SENSe:CALTAB:DATA
Description:
Return a comma-delimited array of integer counts corresponding to all or a portion of the
statistical mode power histogram for the selected channel. Each bin is 32 bits wide, and may
consist of a number from zero (indicating no hits to that power level) to 4 billion (indicating
all hits in the histogram were at that power level). The array will consist of COUNT histo-
gram bins, beginning at bin number INDEX, up to the last bin of the histogram (index =
4095).
Syntax:
SENSe[1|2]:CALTAB:DATA?
Returns:
P(index), P(index+1), P(index+2).... P(index+count)
Valid Modes:
Statistical mode only.
4.5.15 CALibration Subsystem
The CALibration group of commands is used to control automatic zero offset and linearity adjustments to the RF power
sensor and the channel to which it is connected. Zero offset adjustment can be performed any time no RF signal is
applied to the sensor. Linearity calibration requires that the sensor be connected to a calibration signal source
(INTernal 50MHz, EXTernal 1GHz or USER supplied reference), as specified in the CALibration command sequence.
The numeric suffix of the CALibration program mnemonic in the CALibration commands refers to a measurement
channel, that is CALibration1 and CALibration2 represent SENSOR 1 and SENSOR 2 input channels, respectively.
Note that CALibration2 commands will generate an error if used with a single channel Model 4531. Also note that
although CALibration commands do not accept any arguments, all have a query form, which returns an error flag upon
completion of the zero or calibration process. This allows the user to determine when the process has completed, and
whether it was successful.
CALibration:{INTernal|EXTernal}:ZERO
Description:
Performs a sensor zero offset null adjustment of the selected sensor. This procedure should
always be performed immediately before making any measurements within the lowest 10dB
of a sensor’s dynamic range.
Syntax:
CALibration[1|2]:{INTernal|EXTernal}:ZERO[?]
Returns:
0 if successful, 1 otherwise (query form only)
Valid Modes:
Power sensors only. Peak sensors must be AUTOCALed before a zero can be performed.