Create an SMC Fixed Output Measurement

This VB Script example creates a calibrated SMC fixed output measurement using an external, controlled LO. Then a single sweep is taken and data is retrieved.  The external LO is NOT required when using the internal second PNA source for the LO.

Requirements:

Fixed output measurements require that an external LO source be swept and synchronized with the PNA source. FCA performs this synchronization using the external source configuration settings. See Configure an External Source using SCPI.

The fastest, and recommended, method of controlling the LO source is Hardware List (BNC) triggering mode. However, in this mode, FCA channels will not respond to manual triggers. Therefore, the example uses the following mechanism to trigger a sweep:

Write "SENS:SWE:MODE HOLD"    'place channel 1 in HOLD mode
Write "INIT:CONT ON"          'place PNA in internal trigger mode
Write "SENS:SWE:MODE SINGle
Write "*OPC?"                 'wait until the sweep is complete
Read

The SCPI commands in this example are sent over a COM interface using the SCPIStringParser object. You can run a VBScript (*.vbs) program from the PNA using Macros. To run this program, copy the following code into a text editor and save it as a *.vbs file.

option explicit

' Setup infrastructure to use the SCPI over COM

dim app

set app = createobject("Agilentpna835x.application")

dim p

set p = app.scpistringparser

dim returnStr

sub Write (command)

  if len(returnStr) <> 0 then

      err.Raise 55,"Write","Query Unterminated"

  end if

  returnStr = p.parse(command)

end sub

sub WriteIgnoreError(command)

  returnStr = p.Execute(command)

  p.Parse("SYST:ERR?") ' clear error queue

end sub

function Read

  if len(returnStr) = 0 then

    err.Raise 55,"Read","Bad read"

  end if

  Read = returnStr

  returnStr = ""

end function

Write "SYST:PRES"

' When programming in remote mode, hold mode is recommended

Write "SENS:SWE:MODE HOLD"

' Delete the standard measurement

Write "CALC:PAR:DEL:ALL"

' Create an SC21 measurement

Write "CALC:CUST:DEF 'MySC21', 'Scalar Mixer/Converter', 'SC21'"

Write "DISP:WIND:TRACE:FEED 'MySC21'"

Write "CALC:PAR:SEL 'MySC21'"

' Set number of points to 11

Write "SENS:SWE:POIN 11"

' Setup the mixer parameters for a swept LO, fixed output measurement

Write "SENS:MIX:INP:FREQ:START 200e6"

Write "SENS:MIX:INP:FREQ:STOP 700e6"

Write "SENS:MIX:LO:FREQ:MODE Swept"

Write "SENS:MIX:OUTPUT:FREQ:FIX 3.4e9"

Write "SENS:MIX:OUTP:FREQ:SID HIGH"

Write "SENS:MIX:CALC LO_1"

Write "SENS:MIX:INP:POW -17"

Write "SENS:MIX:LO:POW 10"

Write "SENS:MIX:APPLY

' Specify the LO name, for controlled LO.

' This name is setup in the External Source Config Dialog

Write "SENS:MIX:LO:NAME '8360'"

Write "SENS:MIX:APPLY

' Create an S11 in the same channel

Write "CALC:CUST:DEF 'MyS11', 'Scalar Mixer/Converter', 'S11'"

Write "DISP:WIND:TRACE2:FEED 'MyS11'"

Write "CALC:PAR:SEL 'MyS11'"

' Create an IPwr in the same channel

Write "CALC:CUST:DEF 'MyIPwr', 'Scalar Mixer/Converter', 'IPwr'"

Write "DISP:WIND:TRACE3:FEED 'MyIPwr'"

Write "CALC:PAR:SEL 'MyIPwr'"

' Create an OPwr in the same channel

Write "CALC:CUST:DEF 'MyOPwr', 'Scalar Mixer/Converter', 'OPwr'"

Write "CALC:PAR:SEL 'MyOPwr'"

Write "DISP:WIND:TRACE4:FEED 'MyOPwr'"

' Perform a single sweep, synchronously. When *OPC returns, the sweep is done

Write "SENS:SWE:MODE SINGle"

Write "*OPC?"

Read

' Retrieve the SC21 data

Write "CALC:PAR:SEL 'MySC21'"

Write "CALC:DATA? SDATA"

dim data

data = Read()

wscript.echo("SC21=" & data)

'Retrieve the S11 data

Write "CALC:PAR:SEL 'MyS11'"

Write "CALC:DATA? SDATA"

data = Read()

wscript.echo("S11=" & data)

Last Modified:

8-Mar-2011

Updated with new SMC commands A.09.33.