Agilent X-Series Signal Generators SCPI Command Reference
279
Arb Commands
Dual ARB Subsystem–N5172B/82B ([:SOURce]:RADio:ARB)
The preceding example sets the file header RMS noise override value for a file type WFM1, named
Sine_Wave, to .835.
:RAD:ARB:HEADER:NOISe:RMS:OVER "WFM1:Sine_Wave",UNSP
In the second example, the signal generator calculates the RMS, using the waveform file header’s RMS
value. For setting the header’s RMS value, see
“:HEADer:RMS” on page 279
.
The RMS value is expressed in volts.
:HEADer:RMS
Supported
N5172B/82B
[:SOURce]:RADio:ARB:HEADER:RMS "<file_name>",<value>|UNSPecified
[:SOURce]:RADio:ARB:HEADER:RMS? "<file_name>"
This command sets the file header RMS value for the selected waveform file. The X- Series signal
generator uses the RMS value with the dual ARB’s real–time noise function and to optimize the
modulator drive level.
The signal generator reads the RMS value from the file header when a waveform is selected to play.
If the value is unspecified, then it is calculated and stored in the header automatically.
When the waveform file is saved from volatile waveform memory (WFM1) to non–volatile waveform
memory (NVWFM), the RMS value, auto–calculated or user–defined, is also saved.
For setting the header noise carrier RMS override value, see
“:HEADER:NOISe:RMS[:OVERride]” on
page 278
.
"<file_name>"
This variable names the waveform file to which the RMS value will be applied.
The file name variable can designate a file in the WFM1, NVWFM, or SEQ
directories. For information on the file name syntax, refer to
“File Name
Variables” on page 13
.
<value>
This variable is the user–measured RMS value for the specified waveform. The
following figure shows the RMS calculation.
UNSPecified
Using this variable in the command clears the RMS value and sets it to
unspecified. An unspecified RMS value causes the signal generator to calculate the
value when the ARB personality is turned on. The RMS calculation includes
rise/fall times and does not include consecutive zero level samples. DC offsets and
noise are also included in the RMS measurement. But, the Marker values are
not
included in these calculations. Because the signal generator calculation uses so
many factors, you may achieve better results calculating your own RMS value.
Key Entry
Edit Noise RMS Override Unspecified Enter