diff --git a/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.cpp b/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.cpp
index 18d06c1..8cdb025 100644
--- a/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.cpp
+++ b/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.cpp
@@ -6,6 +6,7 @@
 #include "Util/util.h"
 #include "LibreCAL/librecaldialog.h"
 #include "preferences.h"
+#include "Traces/sparamtraceselectordialog.h"
 
 #include "Tools/Eigen/Dense"
 
@@ -408,7 +409,7 @@ void Calibration::correctTraces(std::map<QString, Trace *> traceSet)
     }
 }
 
-void Calibration::edit()
+void Calibration::edit(TraceModel *traceModel)
 {
     auto d = new QDialog();
     d->setAttribute(Qt::WA_DeleteOnClose);
@@ -510,6 +511,10 @@ void Calibration::edit()
         ui->bDelete->setEnabled(ui->table->currentRow() >= 0);
         ui->bMoveUp->setEnabled(ui->table->currentRow() >= 1);
         ui->bMoveDown->setEnabled(ui->table->currentRow() >= 0 && ui->table->currentRow() < ui->table->rowCount() - 1);
+        auto selected = ui->table->selectionModel()->selectedRows();
+        ui->measure->setEnabled(selected.size() > 0);
+        ui->selectMeasurement->setEnabled(traceModel && selected.size() == 1);
+        ui->clearMeasurement->setEnabled(selected.size() > 0);
     };
 
     auto updateMeasurementTable = [=](){
@@ -619,6 +624,35 @@ void Calibration::edit()
         emit startMeasurements(m);
     });
 
+    connect(ui->selectMeasurement, &QPushButton::clicked, [=](){
+        auto selected = ui->table->selectionModel()->selectedRows();
+        if(selected.size() != 1) {
+            InformationBox::ShowError("Unable to select measurement", "Exactly one measurement must be selected");
+            return;
+        }
+        // figure out which S parameters we need
+        auto meas = measurements[selected[0].row()];
+        auto ports = meas->getPorts();
+        if(ports.size() == 0) {
+            InformationBox::ShowError("Unable to select measurement", "Selecting measurements for this type of calibration measurement is not supported");
+            return;
+        }
+        auto selector = new SParamTraceSelectorDialog(*traceModel, ports);
+        connect(selector, &SParamTraceSelectorDialog::tracesSelected, d, [=](std::vector<DeviceDriver::VNAMeasurement> traceMeasurements){
+            clearMeasurements({meas});
+            for(const auto &tm : traceMeasurements) {
+                addMeasurements({meas}, tm);
+            }
+            updateMeasurementTable();
+            updateCalibrationList();
+        });
+        selector->show();
+    });
+    if(!traceModel) {
+        // can not select a measurement if no trace model is supplied
+        ui->selectMeasurement->setEnabled(false);
+    }
+
     connect(this, &Calibration::measurementsUpdated, d, [=](){
         updateMeasurementTable();
         updateCalibrationList();
@@ -665,7 +699,7 @@ void Calibration::edit()
         });
     });
 
-    QObject::connect(ui->table, &QTableWidget::currentCellChanged, updateTableEditButtons);
+    QObject::connect(ui->table, &QTableWidget::itemSelectionChanged, updateTableEditButtons);
 
     auto addMenu = new QMenu();
     for(auto t : CalibrationMeasurement::Base::availableTypes()) {
@@ -802,6 +836,7 @@ Calibration::Point Calibration::computeSOLT(double f)
             auto deltaS = Sideal.get(1,1)*Sideal.get(2,2) - Sideal.get(2,1) * Sideal.get(1,2);
             point.L[i][j] = ((S11 - point.D[i])*(1.0 - point.S[i] * Sideal.get(1,1))-Sideal.get(1,1)*point.R[i])
                     / ((S11 - point.D[i])*(Sideal.get(2,2)-point.S[i]*deltaS)-deltaS*point.R[i]);
+            point.L[i][j] = 0.0;
             point.T[i][j] = (S21 - isolation)*(1.0 - point.S[i]*Sideal.get(1,1) - point.L[i][j]*Sideal.get(2,2) + point.S[i]*point.L[i][j]*deltaS) / Sideal.get(2,1);
             point.I[i][j] = isolation;
         }
diff --git a/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.h b/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.h
index 9efe3c1..49a1b17 100644
--- a/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.h
+++ b/Software/PC_Application/LibreVNA-GUI/Calibration/calibration.h
@@ -46,7 +46,7 @@ public:
     void correctTraces(std::map<QString, Trace*> traceSet);
 
     // Starts the calibration edit dialog, allowing the user to make/delete measurements
-    void edit();
+    void edit(TraceModel *traceModel = nullptr);
 
     Calkit& getKit();
 
diff --git a/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationdialogui.ui b/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationdialogui.ui
index 00cc5ba..e3ae93e 100644
--- a/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationdialogui.ui
+++ b/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationdialogui.ui
@@ -48,7 +48,7 @@
         <item>
          <widget class="QTableWidget" name="table">
           <property name="selectionBehavior">
-           <enum>QAbstractItemView::SelectRows</enum>
+           <enum>QAbstractItemView::SelectionBehavior::SelectRows</enum>
           </property>
           <attribute name="horizontalHeaderStretchLastSection">
            <bool>true</bool>
@@ -148,6 +148,14 @@
             </property>
            </widget>
           </item>
+          <item>
+           <widget class="QPushButton" name="selectMeasurement">
+            <property name="text">
+             <string>Select
+Measurement</string>
+            </property>
+           </widget>
+          </item>
           <item>
            <widget class="QPushButton" name="clearMeasurement">
             <property name="text">
@@ -185,7 +193,7 @@ Kit</string>
           <item>
            <spacer name="verticalSpacer">
             <property name="orientation">
-             <enum>Qt::Vertical</enum>
+             <enum>Qt::Orientation::Vertical</enum>
             </property>
             <property name="sizeHint" stdset="0">
              <size>
@@ -287,7 +295,7 @@ Kit</string>
         <item>
          <spacer name="verticalSpacer_2">
           <property name="orientation">
-           <enum>Qt::Vertical</enum>
+           <enum>Qt::Orientation::Vertical</enum>
           </property>
           <property name="sizeHint" stdset="0">
            <size>
diff --git a/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationmeasurement.h b/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationmeasurement.h
index 8161e8b..51fbf3d 100644
--- a/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationmeasurement.h
+++ b/Software/PC_Application/LibreVNA-GUI/Calibration/calibrationmeasurement.h
@@ -61,6 +61,8 @@ public:
     virtual nlohmann::json toJSON() override;
     virtual void fromJSON(nlohmann::json j) override;
 
+    virtual std::vector<unsigned int> getPorts() = 0;
+
     static bool canMeasureSimultaneously(std::set<Base *> measurements);
     QDateTime getTimestamp() const;
 
@@ -102,6 +104,8 @@ public:
     virtual nlohmann::json toJSON() override;
     virtual void fromJSON(nlohmann::json j) override;
 
+    virtual std::vector<unsigned int> getPorts() override {return {port};}
+
     class Point {
     public:
         double frequency;
@@ -222,6 +226,8 @@ public:
     virtual nlohmann::json toJSON() override;
     virtual void fromJSON(nlohmann::json j) override;
 
+    virtual std::vector<unsigned int> getPorts() override {return {port1, port2};}
+
     class Point {
     public:
         double frequency;
@@ -298,6 +304,8 @@ public:
     virtual nlohmann::json toJSON() override;
     virtual void fromJSON(nlohmann::json j) override;
 
+    virtual std::vector<unsigned int> getPorts() override {return {};}
+
     class Point {
     public:
         double frequency;
diff --git a/Software/PC_Application/LibreVNA-GUI/LibreVNA-GUI.pro b/Software/PC_Application/LibreVNA-GUI/LibreVNA-GUI.pro
index 0337498..c34f55f 100644
--- a/Software/PC_Application/LibreVNA-GUI/LibreVNA-GUI.pro
+++ b/Software/PC_Application/LibreVNA-GUI/LibreVNA-GUI.pro
@@ -116,6 +116,7 @@ HEADERS += \
     Traces/eyediagramplot.h \
     Traces/fftcomplex.h \
     Traces/sparamtraceselector.h \
+    Traces/sparamtraceselectordialog.h \
     Traces/trace.h \
     Traces/traceaxis.h \
     Traces/tracecsvexport.h \
@@ -271,6 +272,7 @@ SOURCES += \
     Traces/eyediagramplot.cpp \
     Traces/fftcomplex.cpp \
     Traces/sparamtraceselector.cpp \
+    Traces/sparamtraceselectordialog.cpp \
     Traces/trace.cpp \
     Traces/traceaxis.cpp \
     Traces/tracecsvexport.cpp \
@@ -389,6 +391,7 @@ FORMS += \
     Traces/eyediagrameditdialog.ui \
     Traces/smithchartdialog.ui \
     Traces/polarchartdialog.ui \
+    Traces/sparamtraceselectordialog.ui \
     Traces/tracecsvexport.ui \
     Traces/traceeditdialog.ui \
     Traces/traceimportdialog.ui \
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.cpp b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.cpp
index 572d6ff..50164f6 100644
--- a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.cpp
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.cpp
@@ -13,7 +13,8 @@ SparamTraceSelector::SparamTraceSelector(const TraceModel &model, std::vector<un
     : model(model),
       empty_allowed(empty_allowed),
       used_ports(used_ports),
-      editablePorts(editablePorts)
+      editablePorts(editablePorts),
+      valid(false)
 {
     createGUI();
     setInitialChoices();
@@ -140,6 +141,7 @@ void SparamTraceSelector::traceSelectionChanged(QComboBox *cb)
 
     } else if(cb->currentIndex() == 0 && points > 0) {
         if(!empty_allowed) {
+            valid = false;
             emit selectionValid(false);
         }
         // Check if all trace selections are set for none
@@ -161,7 +163,8 @@ void SparamTraceSelector::traceSelectionChanged(QComboBox *cb)
     }
     if(empty_allowed) {
         // always valid as soon as at least one trace is selected
-        emit selectionValid(points > 0);
+        valid = points > 0;
+        emit selectionValid(valid);
     } else {
         // actually need to check
         valid = true;
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.h b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.h
index dd6a559..d056a9f 100644
--- a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.h
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselector.h
@@ -16,7 +16,7 @@ public:
     SparamTraceSelector(const TraceModel &model, std::vector<unsigned int> used_ports, bool empty_allowed = false, unsigned int editablePorts = 0);
     SparamTraceSelector(const TraceModel &model, std::set<unsigned int> used_ports, bool empty_allowed = false, unsigned int editablePorts = 0);
 
-    bool isValid();
+    bool isValid() {return valid;}
 
     std::map<QString, Trace*> getTraces();
     unsigned int getPoints() { return points;}
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.cpp b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.cpp
new file mode 100644
index 0000000..647b5d6
--- /dev/null
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.cpp
@@ -0,0 +1,36 @@
+#include "sparamtraceselectordialog.h"
+#include "ui_sparamtraceselectordialog.h"
+
+#include "sparamtraceselector.h"
+#include <QPushButton>
+
+SParamTraceSelectorDialog::SParamTraceSelectorDialog(const TraceModel &model, std::vector<unsigned int> used_ports, bool empty_allowed)
+    : QDialog(nullptr)
+    , ui(new Ui::SParamTraceSelectorDialog)
+{
+    ui->setupUi(this);
+    setAttribute(Qt::WA_DeleteOnClose);
+
+    auto selector = new SparamTraceSelector(model, used_ports, empty_allowed);
+    ui->verticalLayout->replaceWidget(ui->placeholder, selector);
+
+    auto okButton = ui->buttonBox->button(QDialogButtonBox::StandardButton::Ok);
+    connect(selector, &SparamTraceSelector::selectionValid, okButton, &QPushButton::setEnabled);
+    okButton->setEnabled(selector->isValid());
+
+    connect(okButton, &QPushButton::clicked, [=](){
+        auto traces = selector->getTraces();
+        if(traces.size() == 0) {
+            // should not happen
+            reject();
+        }
+        emit tracesSelected(Trace::assembleDatapoints(traces));
+        accept();
+    });
+    connect(ui->buttonBox, &QDialogButtonBox::rejected, this, &SParamTraceSelectorDialog::reject);
+}
+
+SParamTraceSelectorDialog::~SParamTraceSelectorDialog()
+{
+    delete ui;
+}
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.h b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.h
new file mode 100644
index 0000000..e832627
--- /dev/null
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.h
@@ -0,0 +1,27 @@
+#ifndef SPARAMTRACESELECTORDIALOG_H
+#define SPARAMTRACESELECTORDIALOG_H
+
+#include <QDialog>
+
+#include "tracemodel.h"
+
+namespace Ui {
+class SParamTraceSelectorDialog;
+}
+
+class SParamTraceSelectorDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    explicit SParamTraceSelectorDialog(const TraceModel &model, std::vector<unsigned int> used_ports, bool empty_allowed = false);
+    ~SParamTraceSelectorDialog();
+
+signals:
+    void tracesSelected(std::vector<DeviceDriver::VNAMeasurement> traceMeasurements);
+
+private:
+    Ui::SParamTraceSelectorDialog *ui;
+};
+
+#endif // SPARAMTRACESELECTORDIALOG_H
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.ui b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.ui
new file mode 100644
index 0000000..751f0c8
--- /dev/null
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/sparamtraceselectordialog.ui
@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>SParamTraceSelectorDialog</class>
+ <widget class="QDialog" name="SParamTraceSelectorDialog">
+  <property name="windowModality">
+   <enum>Qt::WindowModality::ApplicationModal</enum>
+  </property>
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>494</width>
+    <height>222</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>S-Paramter Trace Selector Dialog</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <widget class="QWidget" name="placeholder" native="true"/>
+   </item>
+   <item>
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="standardButtons">
+      <set>QDialogButtonBox::StandardButton::Cancel|QDialogButtonBox::StandardButton::Ok</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/Software/PC_Application/LibreVNA-GUI/VNA/vna.cpp b/Software/PC_Application/LibreVNA-GUI/VNA/vna.cpp
index 75fb076..e418b30 100644
--- a/Software/PC_Application/LibreVNA-GUI/VNA/vna.cpp
+++ b/Software/PC_Application/LibreVNA-GUI/VNA/vna.cpp
@@ -110,7 +110,7 @@ VNA::VNA(AppWindow *window, QString name)
 
     auto calData = calMenu->addAction("Calibration Measurements");
     connect(calData, &QAction::triggered, [=](){
-        cal.edit();
+        cal.edit(&traceModel);
     });
 
     auto calEditKit = calMenu->addAction("Edit Calibration Kit");
@@ -1375,7 +1375,7 @@ void VNA::ApplyCalibration(Calibration::CalType type)
             // Not all required traces available
             InformationBox::ShowMessageBlocking("Missing calibration measurements", "Not all calibration measurements for this type of calibration have been taken. The calibration can be enabled after the missing measurements have been acquired.");
             DisableCalibration();
-            cal.edit();
+            cal.edit(&traceModel);
         } else {
             // Not all required traces available
             InformationBox::ShowMessageBlocking("Missing calibration measurements", "Not all calibration measurements for this type of calibration have been taken. Please switch to frequency sweep to take these measurements.");
diff --git a/Software/PC_Application/LibreVNA-Test/LibreVNA-Test.pro b/Software/PC_Application/LibreVNA-Test/LibreVNA-Test.pro
index 56cd18a..d16488f 100644
--- a/Software/PC_Application/LibreVNA-Test/LibreVNA-Test.pro
+++ b/Software/PC_Application/LibreVNA-Test/LibreVNA-Test.pro
@@ -110,6 +110,7 @@ SOURCES +=  \
     ../LibreVNA-GUI/Traces/eyediagramplot.cpp \
     ../LibreVNA-GUI/Traces/fftcomplex.cpp \
     ../LibreVNA-GUI/Traces/sparamtraceselector.cpp \
+    ../LibreVNA-GUI/Traces/sparamtraceselectordialog.cpp \
     ../LibreVNA-GUI/Traces/trace.cpp \
     ../LibreVNA-GUI/Traces/traceaxis.cpp \
     ../LibreVNA-GUI/Traces/tracecsvexport.cpp \
@@ -310,6 +311,7 @@ HEADERS += \
     ../LibreVNA-GUI/Traces/eyediagramplot.h \
     ../LibreVNA-GUI/Traces/fftcomplex.h \
     ../LibreVNA-GUI/Traces/sparamtraceselector.h \
+    ../LibreVNA-GUI/Traces/sparamtraceselectordialog.h \
     ../LibreVNA-GUI/Traces/trace.h \
     ../LibreVNA-GUI/Traces/traceaxis.h \
     ../LibreVNA-GUI/Traces/tracecsvexport.h \
@@ -425,6 +427,7 @@ FORMS += \
     ../LibreVNA-GUI/Traces/eyediagrameditdialog.ui \
     ../LibreVNA-GUI/Traces/polarchartdialog.ui \
     ../LibreVNA-GUI/Traces/smithchartdialog.ui \
+    ../LibreVNA-GUI/Traces/sparamtraceselectordialog.ui \
     ../LibreVNA-GUI/Traces/tracecsvexport.ui \
     ../LibreVNA-GUI/Traces/traceeditdialog.ui \
     ../LibreVNA-GUI/Traces/traceimportdialog.ui \