Specifications

Chapter 7 173
Measurement Result Processing
Equivalent Circuit Analysis
7. Measurement Result Processing
100 Dim msg As String
110
120 start_f = "50MHZ"
130 stop_f = "150MHZ"
140 nop = 201
150 trc1 = 1
160 trc2 = 2
170 swp_count = 1
180 equ_model = "E"
190
200 ' E4991A settings
210
220 SCPI.Output "SYST:PRES"
230 '
240 SCPI.Output "DISP:TRAC" & CStr(trc1) & " ON"
250 SCPI.Output "CALC" & CStr(trc1) & ":FORM Z"
260 SCPI.Output "DISP:TRAC" & CStr(trc2) & " ON"
270 SCPI.Output "CALC" & CStr(trc2) & ":FORM ZPH"
280 SCPI.Output "CALC" & CStr(trc2) & ":FORM:UNIT:ANGL DEG"
290
300 SCPI.Output "SWE:TYPE LIN"
310 SCPI.Output "FREQ:STAR " & start_f
320 SCPI.Output "FREQ:STOP " & stop_f
330 SCPI.Output "SWE:POIN " & CStr(nop)
340 SCPI.Output "CALC:AVER:COUN " & CStr(swp_count)
350 SCPI.Output "CALC:AVER ON"
360
370 SCPI.Output "TRIG:SOUR INT"
380 SCPI.Output "INIT:CONT OFF"
390 SCPI.Output "ABOR"
400
410 swp_bool = SCPI.Query("CALC:AVER?")
420 If swp_bool = 1 Then SCPI.Output "CALC:AVER:CLE"
430
440 bool = SingleMeasure
450 If bool = 0 Then
460 MsgBox ("Sweep Aborted")
470 ElseIf bool = 1 Then
480 SCPI.Output "DISP:TRAC" & CStr(trc1) & ":Y:AUTO"
490 SCPI.Output "DISP:TRAC" & CStr(trc2) & ":Y:AUTO"
500
510 SCPI.Output "CALC" & CStr(trc1) & ":EPAR:CIRC " &
equ_model
520 SCPI.Output "CALC" & CStr(trc1) & ":EPAR"
530
540 r1 = SCPI.Query("CALC" & CStr(trc1) & ":DATA:EPAR?
EQR1")
550 c1 = SCPI.Query("CALC" & CStr(trc1) & ":DATA:EPAR?
EQC1")
560 l1 = SCPI.Query("CALC" & CStr(trc1) & ":DATA:EPAR?
EQL1")
570 c0 = SCPI.Query("CALC" & CStr(trc1) & ":DATA:EPAR?
EQC0")
580
590 msg = "Equivarent Circuit Parameters" & vbCrLf & vbCrLf
& "R1=" & CStr(r1) & vbCrLf & "C1=" & CStr(c1) & vbCrLf & "L1=" &
CStr(l1) & vbCrLf & "C0=" & CStr(c0)
600 MsgBox (msg)