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Calibrate Multiple SMC Channels

This example allows you to calibrate multiple SMC channels while connecting the power meter and required standards or ECal module only once.

In the example program:

Modify chans = 2 to indicate the number of channels to calibrate.
You can also change the connector type and cal kit for each port.

The SCPI commands in this example are sent over a COM interface using the SCPIStringParser object. You do NOT need a GPIB connection to run this example.

This VBScript (*.vbs) program can be run as a macro in the VNA. To do this, copy the following code into a text editor file such as Notepad and save it on the VNA hard drive as MultChanCal.vbs. Learn how to setup and run the macro.

Dim app

Dim scpi

Dim chans

Dim i

Dim steps

Dim desc

' Create / Get the VNA application.

Set app = CreateObject("AgilentPNA835x.Application")

Set scpi = app.ScpiStringParser

app.Preset

' Set number of channels to create

chans = 2

ReDim calset(chans - 1)

For i = 1 To chans

chanStr = CStr(i+1) ' calibrate on channels 2 and 3

Dim parm, measName, sens, calc

parm = "S" & CStr(i) & CStr(i)

measName = "My" & parm

sens = "SENS" & chanStr

calc = "CALC" & chanStr

scpi.Parse calc & ":CUST:DEF '" & measName & "', 'Scalar Mixer/Converter', '" & parm & "'"

'Setup the new measurement as the 2nd trace in the active window

scpi.Parse "DISP:WIND:TRAC" & chanStr & ":FEED '" & measName & "'"

'Make the new trace the active measurement

scpi.Parse calc & ":PAR:SEL '" & measName & "'"

'--------------Perform A FCA Mixer Calibration-------------

'Set ports and cal kits for 2 port calibration portion

scpi.Parse sens & ":CORR:COLL:GUID:CONN:PORT1:SEL ""APC 3.5 male"""

scpi.Parse sens & ":CORR:COLL:GUID:CONN:PORT2:SEL ""APC 3.5 female"""

scpi.Parse sens & ":CORR:COLL:GUID:CKIT:PORT1:SEL ""85052C"""

scpi.Parse sens & ":CORR:COLL:GUID:CKIT:PORT2:SEL ""85052C"""

'ECal modules are specified with the same command

' scpi.Parse sens & ":CORR:COLL:GUID:CKIT:PORT1:SEL ""N4691-60004 ECal"""

' scpi.Parse sens & ":CORR:COLL:GUID:CKIT:PORT2:SEL ""N4691-60004 ECal"""

'Specify the thru measurement method.

scpi.Parse sens & ":CORR:COLL:GUID:PATH:TMET 1,2,""DEFINED THRU"""

'Omit the isolation part of the 2-port cal

scpi.Parse sens & ":CORR:COLL:GUID:ISOL NONE"

'Initialize an SMC guided calibration.

scpi.Parse sens & ":CORR:COLL:GUID:INIT"

'Determine the number of steps required to complete the calibration.

steps = scpi.Parse (sens & ":CORR:COLL:GUID:STEP?")

For j = 1 To CInt(steps)

'Display the prompt for each step

desc = scpi.Parse(sens & ":CORR:COLL:GUID:DESC? " & CStr(j))

MsgBox (desc)

'Measure the same standard for each channel

For i = 1 To chans

chanStr = CStr(i+1) ' channel number as string

scpi.Parse "SENS" & chanStr & ":CORR:COLL:GUID:ACQ STAN" & CStr(j)

opc_comp = scpi.Parse("*OPC?")

'Finish the cal and save the calsets

For i = 1 To chans

calset(i - 1) = scpi.Parse("SENS" & CStr(i+1) & ":CORR:COLL:GUID:SAVE ON")

MsgBox ("SMC Cals Complete!")