diff --git a/Software/PC_Application/Application.pro b/Software/PC_Application/Application.pro
index 828af30..b0337a0 100644
--- a/Software/PC_Application/Application.pro
+++ b/Software/PC_Application/Application.pro
@@ -5,6 +5,7 @@ HEADERS += \
     Calibration/calkit.h \
     Calibration/calkitdialog.h \
     Calibration/measurementmodel.h \
+    CustomWidgets/colorpickerbutton.h \
     CustomWidgets/siunitedit.h \
     CustomWidgets/tilewidget.h \
     CustomWidgets/toggleswitch.h \
@@ -47,6 +48,7 @@ SOURCES += \
     Calibration/calkit.cpp \
     Calibration/calkitdialog.cpp \
     Calibration/measurementmodel.cpp \
+    CustomWidgets/colorpickerbutton.cpp \
     CustomWidgets/qwtplotpiecewisecurve.cpp \
     CustomWidgets/siunitedit.cpp \
     CustomWidgets/tilewidget.cpp \
diff --git a/Software/PC_Application/CustomWidgets/colorpickerbutton.cpp b/Software/PC_Application/CustomWidgets/colorpickerbutton.cpp
new file mode 100644
index 0000000..c6fe35f
--- /dev/null
+++ b/Software/PC_Application/CustomWidgets/colorpickerbutton.cpp
@@ -0,0 +1,35 @@
+#include "colorpickerbutton.h"
+#include <QColorDialog>
+
+ColorPickerButton::ColorPickerButton(QWidget *parent)
+    : QPushButton(parent)
+{
+    color = Qt::white;
+    connect(this, &ColorPickerButton::clicked, this, &ColorPickerButton::changeColor);
+    updateBackground();
+}
+
+void ColorPickerButton::setColor(const QColor &color)
+{
+    this->color = color;
+    updateBackground();
+}
+
+const QColor &ColorPickerButton::getColor()
+{
+    return color;
+}
+
+void ColorPickerButton::changeColor()
+{
+    auto newColor = QColorDialog::getColor(color, parentWidget(), "Select color", QColorDialog::DontUseNativeDialog);
+    if(newColor.isValid() && newColor != color) {
+        setColor(newColor);
+        emit colorChanged(newColor);
+    }
+}
+
+void ColorPickerButton::updateBackground()
+{
+    setStyleSheet("background-color:"+color.name());
+}
diff --git a/Software/PC_Application/CustomWidgets/colorpickerbutton.h b/Software/PC_Application/CustomWidgets/colorpickerbutton.h
new file mode 100644
index 0000000..a410325
--- /dev/null
+++ b/Software/PC_Application/CustomWidgets/colorpickerbutton.h
@@ -0,0 +1,23 @@
+#ifndef COLORPICKERBUTTON_H
+#define COLORPICKERBUTTON_H
+
+#include <QPushButton>
+
+class ColorPickerButton : public QPushButton
+{
+    Q_OBJECT
+public:
+    ColorPickerButton(QWidget *parent = nullptr);
+
+    void setColor(const QColor& color);
+    const QColor& getColor();
+signals:
+    void colorChanged(const QColor& color);
+private slots:
+    void changeColor();
+private:
+    void updateBackground();
+    QColor color;
+};
+
+#endif // COLORPICKERBUTTON_H
diff --git a/Software/PC_Application/Generator/generator.cpp b/Software/PC_Application/Generator/generator.cpp
index 866ae37..ae274ed 100644
--- a/Software/PC_Application/Generator/generator.cpp
+++ b/Software/PC_Application/Generator/generator.cpp
@@ -6,6 +6,8 @@ Generator::Generator(AppWindow *window)
 {
     central = new SignalgeneratorWidget();
 
+    auto pref = Preferences::getInstance();
+
     // set initial values
     if(pref.Startup.RememberSweepSettings) {
         QSettings s;
diff --git a/Software/PC_Application/SpectrumAnalyzer/spectrumanalyzer.cpp b/Software/PC_Application/SpectrumAnalyzer/spectrumanalyzer.cpp
index b5a9636..f6b5430 100644
--- a/Software/PC_Application/SpectrumAnalyzer/spectrumanalyzer.cpp
+++ b/Software/PC_Application/SpectrumAnalyzer/spectrumanalyzer.cpp
@@ -184,6 +184,7 @@ SpectrumAnalyzer::SpectrumAnalyzer(AppWindow *window)
     qRegisterMetaType<Protocol::SpectrumAnalyzerResult>("SpectrumResult");
 
     // Set initial sweep settings
+    auto pref = Preferences::getInstance();
     if(pref.Startup.RememberSweepSettings) {
         LoadSweepSettings();
     } else {
@@ -364,6 +365,7 @@ void SpectrumAnalyzer::ConstrainAndUpdateFrequencies()
 void SpectrumAnalyzer::LoadSweepSettings()
 {
     QSettings s;
+    auto pref = Preferences::getInstance();
     settings.f_start = s.value("SAStart", pref.Startup.SA.start).toULongLong();
     settings.f_stop = s.value("SAStop", pref.Startup.SA.stop).toULongLong();
     ConstrainAndUpdateFrequencies();
diff --git a/Software/PC_Application/Traces/tracebodeplot.cpp b/Software/PC_Application/Traces/tracebodeplot.cpp
index cceafa1..063e9c2 100644
--- a/Software/PC_Application/Traces/tracebodeplot.cpp
+++ b/Software/PC_Application/Traces/tracebodeplot.cpp
@@ -1,6 +1,5 @@
 #include "tracebodeplot.h"
 #include <QGridLayout>
-#include <qwt_plot_grid.h>
 #include "qwtplotpiecewisecurve.h"
 #include "qwt_series_data.h"
 #include "trace.h"
@@ -13,9 +12,12 @@
 #include <qwt_symbol.h>
 #include <qwt_picker_machine.h>
 #include "bodeplotaxisdialog.h"
+#include <preferences.h>
 
 using namespace std;
 
+set<TraceBodePlot*> TraceBodePlot::allPlots;
+
 static double AxisTransformation(TraceBodePlot::YAxisType type, complex<double> data) {
     switch(type) {
     case TraceBodePlot::YAxisType::Magnitude: return 20*log10(abs(data)); break;
@@ -58,16 +60,14 @@ TraceBodePlot::TraceBodePlot(TraceModel &model, QWidget *parent)
       selectedMarker(nullptr)
 {
     plot = new QwtPlot(this);
-    plot->setCanvasBackground(Background);
-    auto pal = plot->palette();
-    pal.setColor(QPalette::Window, Background);
-    pal.setColor(QPalette::WindowText, Border);
-    pal.setColor(QPalette::Text, Border);
+
     auto canvas = new QwtPlotCanvas(plot);
     canvas->setFrameStyle(QFrame::Plain);
     plot->setCanvas(canvas);
-    plot->setPalette(pal);
     plot->setAutoFillBackground(true);
+    grid = new QwtPlotGrid();
+    grid->attach(plot);
+    setColorFromPreferences();
 
     auto selectPicker = new BodeplotPicker(plot->xBottom, plot->yLeft, QwtPicker::NoRubberBand, QwtPicker::ActiveOnly, plot->canvas());
     selectPicker->setStateMachine(new QwtPickerClickPointMachine);
@@ -81,15 +81,11 @@ TraceBodePlot::TraceBodePlot(TraceModel &model, QWidget *parent)
     // Marker movement
     connect(drawPicker, SIGNAL(moved(QPointF)), this, SLOT(moved(QPointF)));
 
-    QwtPlotGrid *grid = new QwtPlotGrid();
-    grid->setMajorPen(QPen(Divisions, 1.0, Qt::DotLine));
-    grid->attach(plot);
     auto layout = new QGridLayout;
     layout->addWidget(plot);
     layout->setContentsMargins(0, 0, 0, 0);
     setLayout(layout);
     plot->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
-//    plot->plotLayout()->setAlignCanvasToScales(true);
     initializeTraceInfo(model);
     setAutoFillBackground(true);
 
@@ -101,6 +97,8 @@ TraceBodePlot::TraceBodePlot(TraceModel &model, QWidget *parent)
     setXAxis(true, 0, 6000000000, 600000000);
     // get notified when the span changes
     connect(&model, &TraceModel::SpanChanged, this, qOverload<double, double>(&TraceBodePlot::setXAxis));
+
+    allPlots.insert(this);
 }
 
 TraceBodePlot::~TraceBodePlot()
@@ -111,6 +109,7 @@ TraceBodePlot::~TraceBodePlot()
         }
     }
     delete drawPicker;
+    allPlots.erase(this);
 }
 
 void TraceBodePlot::setXAxis(double min, double max)
@@ -187,32 +186,16 @@ void TraceBodePlot::enableTrace(Trace *t, bool enabled)
     }
 }
 
+void TraceBodePlot::updateGraphColors()
+{
+    for(auto p : allPlots) {
+        p->setColorFromPreferences();
+    }
+}
+
 void TraceBodePlot::updateContextMenu()
 {
     contextmenu->clear();
-//    for(int axis = 0;axis < 2;axis++) {
-//        QMenu *axisMenu;
-//        if(axis == 0) {
-//            axisMenu = contextmenu->addMenu("Primary Axis");
-//        } else {
-//            axisMenu = contextmenu->addMenu("Secondary Axis");
-//        }
-//        auto group = new QActionGroup(this);
-//        for(int i=0;i<(int) YAxisType::Last;i++) {
-//            auto action = new QAction(AxisTypeToName((YAxisType) i));
-//            action->setCheckable(true);
-//            group->addAction(action);
-//            if(YAxis[axis].type == (YAxisType) i) {
-//                action->setChecked(true);
-//            }
-//            connect(action, &QAction::triggered, [=](bool active) {
-//                if(active) {
-//                    setYAxisType(axis, (YAxisType) i);
-//                }
-//            });
-//        }
-//        axisMenu->addActions(group->actions());
-//    }
     auto setup = new QAction("Axis setup...");
     connect(setup, &QAction::triggered, [this]() {
         auto setup = new BodeplotAxisDialog(this);
@@ -483,13 +466,18 @@ void TraceBodePlot::moved(const QPointF pos)
     if(!selectedMarker || !selectedCurve) {
         return;
     }
-//        int index = selectedCurve->closestPoint(pos.toPoint());
-//        qDebug() << index;
-//        if(index < 0) {
-//            // unable to find closest point
-//            return;
-//        }
-//        selectedMarker->setFrequency(selectedCurve->sample(index).x());
     selectedMarker->setFrequency(pos.x());
 }
 
+void TraceBodePlot::setColorFromPreferences()
+{
+    auto pref = Preferences::getInstance();
+    plot->setCanvasBackground(pref.General.graphColors.background);
+    auto pal = plot->palette();
+    pal.setColor(QPalette::Window, pref.General.graphColors.background);
+    pal.setColor(QPalette::WindowText, pref.General.graphColors.axis);
+    pal.setColor(QPalette::Text, pref.General.graphColors.axis);
+    plot->setPalette(pal);
+    grid->setPen(pref.General.graphColors.divisions);
+}
+
diff --git a/Software/PC_Application/Traces/tracebodeplot.h b/Software/PC_Application/Traces/tracebodeplot.h
index b65a588..0564427 100644
--- a/Software/PC_Application/Traces/tracebodeplot.h
+++ b/Software/PC_Application/Traces/tracebodeplot.h
@@ -7,7 +7,7 @@
 #include <qwt_plot_curve.h>
 #include <qwt_series_data.h>
 #include <qwt_plot_marker.h>
-
+#include <qwt_plot_grid.h>
 #include <qwt_plot_picker.h>
 
 // Derived plotpicker, exposing transformation functions
@@ -45,6 +45,9 @@ public:
     void setXAxis(bool autorange, double min, double max, double div);
     void enableTrace(Trace *t, bool enabled) override;
 
+    // Applies potentially changed colors to all bodeplots
+    static void updateGraphColors();
+
 protected:
     virtual void updateContextMenu();
     virtual bool supported(Trace *t);
@@ -60,6 +63,7 @@ private slots:
     void clicked(const QPointF pos);
     void moved(const QPointF pos);
 private:
+    void setColorFromPreferences();
     QString AxisTypeToName(YAxisType type);
     void enableTraceAxis(Trace *t, int axis, bool enabled);
     bool supported(Trace *t, YAxisType type);
@@ -89,10 +93,14 @@ private:
     std::map<Trace*, CurveData> curves[2];
     std::map<TraceMarker*, QwtPlotMarker*> markers;
     QwtPlot *plot;
+    QwtPlotGrid *grid;
     TraceMarker *selectedMarker;
     QwtPlotCurve *selectedCurve;
 
     BodeplotPicker *drawPicker;
+
+    // keep track of all created plots for changing colors
+    static std::set<TraceBodePlot*> allPlots;
 };
 
 #endif // TRACEBODEPLOT_H
diff --git a/Software/PC_Application/Traces/traceeditdialog.cpp b/Software/PC_Application/Traces/traceeditdialog.cpp
index 4f42a9d..31e9405 100644
--- a/Software/PC_Application/Traces/traceeditdialog.cpp
+++ b/Software/PC_Application/Traces/traceeditdialog.cpp
@@ -10,7 +10,10 @@ TraceEditDialog::TraceEditDialog(Trace &t, QWidget *parent) :
 {
     ui->setupUi(this);
     ui->name->setText(t.name());
-    setColor(trace.color());
+    ui->color->setColor(trace.color());
+    connect(ui->color, &ColorPickerButton::colorChanged, [=](const QColor& color){
+       trace.setColor(color);
+    });
 
     ui->GSource->setId(ui->bLive, 0);
     ui->GSource->setId(ui->bFile, 1);
@@ -98,13 +101,6 @@ TraceEditDialog::~TraceEditDialog()
     delete ui;
 }
 
-void TraceEditDialog::on_color_clicked()
-{
-    auto color = QColorDialog::getColor(trace.color(), this, "Select color", QColorDialog::DontUseNativeDialog);
-    setColor(color);
-}
-
-
 void TraceEditDialog::on_buttonBox_accepted()
 {
     trace.setName(ui->name->text());
@@ -139,13 +135,3 @@ void TraceEditDialog::on_buttonBox_accepted()
     }
     delete this;
 }
-
-void TraceEditDialog::setColor(QColor c)
-{
-    QPalette pal = ui->color->palette();
-    pal.setColor(QPalette::Button, c);
-    ui->color->setAutoFillBackground(true);
-    ui->color->setPalette(pal);
-    ui->color->update();
-    trace.setColor(c);
-}
diff --git a/Software/PC_Application/Traces/traceeditdialog.h b/Software/PC_Application/Traces/traceeditdialog.h
index 6149886..9f16d10 100644
--- a/Software/PC_Application/Traces/traceeditdialog.h
+++ b/Software/PC_Application/Traces/traceeditdialog.h
@@ -17,11 +17,9 @@ public:
     ~TraceEditDialog();
 
 private slots:
-    void on_color_clicked();
     void on_buttonBox_accepted();
 
 private:
-    void setColor(QColor c);
     Ui::TraceEditDialog *ui;
     Trace &trace;
     bool VNAtrace;
diff --git a/Software/PC_Application/Traces/traceeditdialog.ui b/Software/PC_Application/Traces/traceeditdialog.ui
index 1f33371..2fb98df 100644
--- a/Software/PC_Application/Traces/traceeditdialog.ui
+++ b/Software/PC_Application/Traces/traceeditdialog.ui
@@ -37,7 +37,7 @@
       </widget>
      </item>
      <item row="1" column="1">
-      <widget class="QPushButton" name="color">
+      <widget class="ColorPickerButton" name="color">
        <property name="sizePolicy">
         <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
          <horstretch>0</horstretch>
@@ -162,6 +162,11 @@
    <header>CustomWidgets/touchstoneimport.h</header>
    <container>1</container>
   </customwidget>
+  <customwidget>
+   <class>ColorPickerButton</class>
+   <extends>QPushButton</extends>
+   <header>CustomWidgets/colorpickerbutton.h</header>
+  </customwidget>
  </customwidgets>
  <resources/>
  <connections>
diff --git a/Software/PC_Application/Traces/tracemarker.cpp b/Software/PC_Application/Traces/tracemarker.cpp
index 9c92f44..210e7de 100644
--- a/Software/PC_Application/Traces/tracemarker.cpp
+++ b/Software/PC_Application/Traces/tracemarker.cpp
@@ -117,6 +117,8 @@ QString TraceMarker::readableData()
             return ret;
         }
         break;
+    default:
+        return "Unknown marker type";
     }
 }
 
@@ -378,6 +380,7 @@ void TraceMarker::adjustSettings(double value)
     case Type::Delta:
     default:
         setFrequency(value);
+        /* no break */
     case Type::Lowpass:
     case Type::Highpass:
     case Type::Bandpass:
@@ -396,6 +399,7 @@ void TraceMarker::update()
     }
     switch(type) {
     case Type::Manual:
+    case Type::Delta:
         // nothing to do
         break;
     case Type::Maximum:
diff --git a/Software/PC_Application/Traces/traceplot.cpp b/Software/PC_Application/Traces/traceplot.cpp
index 8248ecf..63dbfca 100644
--- a/Software/PC_Application/Traces/traceplot.cpp
+++ b/Software/PC_Application/Traces/traceplot.cpp
@@ -1,8 +1,8 @@
 #include "traceplot.h"
 
-const QColor TracePlot::Background = QColor(0,0,0);
-const QColor TracePlot::Border = QColor(255,255,255);
-const QColor TracePlot::Divisions = QColor(255,255,255);
+//const QColor TracePlot::Background = QColor(0,0,0);
+//const QColor TracePlot::Border = QColor(255,255,255);
+//const QColor TracePlot::Divisions = QColor(255,255,255);
 #include "tracemarker.h"
 
 std::set<TracePlot*> TracePlot::plots;
diff --git a/Software/PC_Application/Traces/traceplot.h b/Software/PC_Application/Traces/traceplot.h
index 0270616..856f82e 100644
--- a/Software/PC_Application/Traces/traceplot.h
+++ b/Software/PC_Application/Traces/traceplot.h
@@ -25,9 +25,9 @@ signals:
     void deleted(TracePlot*);
 
 protected:
-    static const QColor Background;// = QColor(0,0,0);
-    static const QColor Border;// = QColor(255,255,255);
-    static const QColor Divisions;// = QColor(255,255,255);
+//    static const QColor Background;// = QColor(0,0,0);
+//    static const QColor Border;// = QColor(255,255,255);
+//    static const QColor Divisions;// = QColor(255,255,255);
     static constexpr int MinUpdateInterval = 100;
     // need to be called in derived class constructor
     void initializeTraceInfo(TraceModel &model);
diff --git a/Software/PC_Application/Traces/tracesmithchart.cpp b/Software/PC_Application/Traces/tracesmithchart.cpp
index 07a5828..08e89a4 100644
--- a/Software/PC_Application/Traces/tracesmithchart.cpp
+++ b/Software/PC_Application/Traces/tracesmithchart.cpp
@@ -4,6 +4,7 @@
 #include <math.h>
 #include "tracemarker.h"
 #include <QDebug>
+#include "preferences.h"
 
 using namespace std;
 
@@ -92,13 +93,15 @@ void TraceSmithChart::draw(QPainter * painter, double width_factor) {
 //    painter->setFont(font);
 //    painter->drawText(-512, -512, title);
 
+    auto pref = Preferences::getInstance();
+
     // Outer circle
-    painter->setPen(QPen(Border, 1.5 * width_factor));
+    painter->setPen(QPen(pref.General.graphColors.axis, 1.5 * width_factor));
     QRectF rectangle(-smithCoordMax, -smithCoordMax, 2*smithCoordMax, 2*smithCoordMax);
     painter->drawArc(rectangle, 0, 5760);
 
     constexpr int Circles = 6;
-    painter->setPen(QPen(Divisions, 0.5 * width_factor, Qt::DashLine));
+    painter->setPen(QPen(pref.General.graphColors.divisions, 0.5 * width_factor, Qt::DashLine));
     for(int i=1;i<Circles;i++) {
         rectangle.adjust(2*smithCoordMax/Circles, smithCoordMax/Circles, 0, -smithCoordMax/Circles);
         painter->drawArc(rectangle, 0, 5760);
@@ -162,10 +165,11 @@ void TraceSmithChart::replot()
 
 void TraceSmithChart::paintEvent(QPaintEvent * /* the event */)
 {
+    auto pref = Preferences::getInstance();
     QPainter painter(this);
     painter.setRenderHint(QPainter::Antialiasing);
-    painter.setBackground(QBrush(Background));
-    painter.fillRect(0, 0, width(), height(), QBrush(Background));
+    painter.setBackground(QBrush(pref.General.graphColors.background));
+    painter.fillRect(0, 0, width(), height(), QBrush(pref.General.graphColors.background));
 
     double side = qMin(width(), height()) * screenUsage;
 
diff --git a/Software/PC_Application/VNA/vna.cpp b/Software/PC_Application/VNA/vna.cpp
index ef683d1..84396be 100644
--- a/Software/PC_Application/VNA/vna.cpp
+++ b/Software/PC_Application/VNA/vna.cpp
@@ -417,6 +417,7 @@ VNA::VNA(AppWindow *window)
     qRegisterMetaType<Protocol::Datapoint>("Datapoint");
 
     // Set initial sweep settings
+    auto pref = Preferences::getInstance();
     if(pref.Acquisition.alwaysExciteBothPorts) {
         settings.excitePort1 = 1;
         settings.excitePort2 = 1;
@@ -539,7 +540,7 @@ void VNA::UpdateStatusPanel()
 
 void VNA::SettingsChanged()
 {
-    settings.suppressPeaks = pref.Acquisition.suppressPeaks ? 1 : 0;
+    settings.suppressPeaks = Preferences::getInstance().Acquisition.suppressPeaks ? 1 : 0;
     if(window->getDevice()) {
         window->getDevice()->Configure(settings);
     }
@@ -675,8 +676,7 @@ void VNA::SetAveraging(unsigned int averages)
 
 void VNA::ExcitationRequired(bool port1, bool port2)
 {
-    qDebug() << pref.Acquisition.alwaysExciteBothPorts;
-    if(pref.Acquisition.alwaysExciteBothPorts) {
+    if(Preferences::getInstance().Acquisition.alwaysExciteBothPorts) {
         port1 = true;
         port2 = true;
     }
@@ -771,6 +771,7 @@ void VNA::ConstrainAndUpdateFrequencies()
 
 void VNA::LoadSweepSettings()
 {
+    auto pref = Preferences::getInstance();
     QSettings s;
     settings.f_start = s.value("SweepStart", pref.Startup.DefaultSweep.start).toULongLong();
     settings.f_stop = s.value("SweepStop", pref.Startup.DefaultSweep.stop).toULongLong();
diff --git a/Software/PC_Application/appwindow.cpp b/Software/PC_Application/appwindow.cpp
index 8fb1968..1b7f3a1 100644
--- a/Software/PC_Application/appwindow.cpp
+++ b/Software/PC_Application/appwindow.cpp
@@ -55,7 +55,7 @@ AppWindow::AppWindow(QWidget *parent)
     QCoreApplication::setOrganizationName("VNA");
     QCoreApplication::setApplicationName("Application");
 
-    pref.load();
+    Preferences::getInstance().load();
     device = nullptr;
 
     ui->setupUi(this);
@@ -108,9 +108,9 @@ AppWindow::AppWindow(QWidget *parent)
         }
     });
     connect(ui->actionPreferences, &QAction::triggered, [=](){
-       qDebug() << pref.Acquisition.alwaysExciteBothPorts;
-       pref.edit();
-       qDebug() << pref.Acquisition.alwaysExciteBothPorts;
+        Preferences::getInstance().edit();
+        // settings might have changed, update necessary stuff
+        TraceBodePlot::updateGraphColors();
     });
 
     setWindowTitle("VNA");
@@ -131,7 +131,7 @@ AppWindow::AppWindow(QWidget *parent)
     qRegisterMetaType<Protocol::Datapoint>("Datapoint");
 
     // List available devices
-    if(UpdateDeviceList() && pref.Startup.ConnectToFirstDevice) {
+    if(UpdateDeviceList() && Preferences::getInstance().Startup.ConnectToFirstDevice) {
         // at least one device available
         ConnectToDevice();
     }
@@ -145,7 +145,7 @@ void AppWindow::closeEvent(QCloseEvent *event)
     if(Mode::getActiveMode()) {
         Mode::getActiveMode()->deactivate();
     }
-    pref.store();
+    Preferences::getInstance().store();
     QMainWindow::closeEvent(event);
 }
 
@@ -244,11 +244,6 @@ void AppWindow::CreateToolbars()
     tb_reference->setObjectName("Reference Toolbar");
 }
 
-Preferences &AppWindow::getPreferenceRef()
-{
-    return pref;
-}
-
 int AppWindow::UpdateDeviceList()
 {
     deviceActionGroup->setExclusive(true);
diff --git a/Software/PC_Application/appwindow.h b/Software/PC_Application/appwindow.h
index ba8c60e..32dd158 100644
--- a/Software/PC_Application/appwindow.h
+++ b/Software/PC_Application/appwindow.h
@@ -34,8 +34,6 @@ public:
     QStackedWidget *getCentral() const;
     Device *getDevice() const;
 
-    Preferences &getPreferenceRef();
-
 protected:
     void closeEvent(QCloseEvent *event) override;
 private slots:
@@ -60,8 +58,6 @@ private:
         } reference;
     } toolbars;
 
-    Preferences pref;
-
     Device *device;
     DeviceLog deviceLog;
     QString deviceSerial;
diff --git a/Software/PC_Application/mode.cpp b/Software/PC_Application/mode.cpp
index 5b05762..977c981 100644
--- a/Software/PC_Application/mode.cpp
+++ b/Software/PC_Application/mode.cpp
@@ -10,7 +10,6 @@ QButtonGroup* Mode::modeButtonGroup = nullptr;
 
 Mode::Mode(AppWindow *window, QString name)
     : window(window),
-      pref(window->getPreferenceRef()),
       name(name),
       central(nullptr)
 {
diff --git a/Software/PC_Application/mode.h b/Software/PC_Application/mode.h
index eeb558d..d747c53 100644
--- a/Software/PC_Application/mode.h
+++ b/Software/PC_Application/mode.h
@@ -29,8 +29,6 @@ protected:
     std::set<QToolBar*> toolbars;
     std::set<QDockWidget*> docks;
 
-    Preferences &pref;
-
 private:
     static Mode *activeMode;
     static QWidget *cornerWidget;
diff --git a/Software/PC_Application/preferences.cpp b/Software/PC_Application/preferences.cpp
index e4457b1..3dd3128 100644
--- a/Software/PC_Application/preferences.cpp
+++ b/Software/PC_Application/preferences.cpp
@@ -7,6 +7,8 @@
 
 using namespace std;
 
+Preferences Preferences::instance;
+
 PreferencesDialog::PreferencesDialog(Preferences *pref, QWidget *parent) :
     QDialog(parent),
     ui(new Ui::PreferencesDialog),
@@ -100,6 +102,9 @@ PreferencesDialog::PreferencesDialog(Preferences *pref, QWidget *parent) :
         p->Startup.SA.signalID = ui->StartupSASignalID->isChecked();
         p->Acquisition.alwaysExciteBothPorts = ui->AcquisitionAlwaysExciteBoth->isChecked();
         p->Acquisition.suppressPeaks = ui->AcquisitionSuppressPeaks->isChecked();
+        p->General.graphColors.background = ui->GeneralGraphBackground->getColor();
+        p->General.graphColors.axis = ui->GeneralGraphAxis->getColor();
+        p->General.graphColors.divisions = ui->GeneralGraphDivisions->getColor();
         accept();
     });
 
@@ -135,6 +140,10 @@ void PreferencesDialog::setInitialGUIState()
 
     ui->AcquisitionAlwaysExciteBoth->setChecked(p->Acquisition.alwaysExciteBothPorts);
     ui->AcquisitionSuppressPeaks->setChecked(p->Acquisition.suppressPeaks);
+
+    ui->GeneralGraphBackground->setColor(p->General.graphColors.background);
+    ui->GeneralGraphAxis->setColor(p->General.graphColors.axis);
+    ui->GeneralGraphDivisions->setColor(p->General.graphColors.divisions);
 }
 
 void Preferences::load()
diff --git a/Software/PC_Application/preferences.h b/Software/PC_Application/preferences.h
index 7c2bdde..43831c9 100644
--- a/Software/PC_Application/preferences.h
+++ b/Software/PC_Application/preferences.h
@@ -30,6 +30,9 @@ private:
 
 class Preferences {
 public:
+    static Preferences& getInstance() {
+        return instance;
+    }
     void load();
     void store();
     void edit();
@@ -62,13 +65,22 @@ public:
         bool alwaysExciteBothPorts;
         bool suppressPeaks;
     } Acquisition;
+    struct {
+        struct {
+            QColor background;
+            QColor axis;
+            QColor divisions;
+        } graphColors;
+    } General;
 private:
+    Preferences(){};
+    static Preferences instance;
     using SettingDescription = struct {
         QPointerVariant var;
         QString name;
         QVariant def;
     };
-    const std::array<SettingDescription, 17> descr = {{
+    const std::array<SettingDescription, 20> descr = {{
         {&Startup.ConnectToFirstDevice, "Startup.ConnectToFirstDevice", true},
         {&Startup.RememberSweepSettings, "Startup.RememberSweepSettings", false},
         {&Startup.DefaultSweep.start, "Startup.DefaultSweep.start", 1000000.0},
@@ -85,7 +97,10 @@ private:
         {&Startup.SA.detector, "Startup.SA.detector", 0},
         {&Startup.SA.signalID, "Startup.SA.signalID", true},
         {&Acquisition.alwaysExciteBothPorts, "Acquisition.alwaysExciteBothPorts", true},
-        {&Acquisition.suppressPeaks, "Acquisition.suppressPeaks", true},                               
+        {&Acquisition.suppressPeaks, "Acquisition.suppressPeaks", true},
+        {&General.graphColors.background, "General.graphColors.background", QColor(Qt::black)},
+        {&General.graphColors.axis, "General.graphColors.axis", QColor(Qt::white)},
+        {&General.graphColors.divisions, "General.graphColors.divisions", QColor(Qt::gray)},
     }};
 };
 
diff --git a/Software/PC_Application/preferencesdialog.ui b/Software/PC_Application/preferencesdialog.ui
index 14e3a3f..8284d52 100644
--- a/Software/PC_Application/preferencesdialog.ui
+++ b/Software/PC_Application/preferencesdialog.ui
@@ -51,6 +51,11 @@
          <string>Acquisition</string>
         </property>
        </item>
+       <item>
+        <property name="text">
+         <string>General</string>
+        </property>
+       </item>
       </widget>
      </item>
      <item>
@@ -68,7 +73,7 @@
         </size>
        </property>
        <property name="currentIndex">
-        <number>0</number>
+        <number>2</number>
        </property>
        <widget class="QWidget" name="Startup">
         <layout class="QHBoxLayout" name="horizontalLayout_4">
@@ -449,6 +454,95 @@
          </item>
         </layout>
        </widget>
+       <widget class="QWidget" name="General">
+        <layout class="QHBoxLayout" name="horizontalLayout_6">
+         <item>
+          <layout class="QHBoxLayout" name="horizontalLayout_5">
+           <item>
+            <layout class="QVBoxLayout" name="verticalLayout_4">
+             <item>
+              <widget class="QGroupBox" name="groupBox_5">
+               <property name="title">
+                <string>Graph colors</string>
+               </property>
+               <layout class="QFormLayout" name="formLayout_4">
+                <item row="0" column="0">
+                 <widget class="QLabel" name="label_15">
+                  <property name="text">
+                   <string>Background:</string>
+                  </property>
+                 </widget>
+                </item>
+                <item row="0" column="1">
+                 <widget class="ColorPickerButton" name="GeneralGraphBackground">
+                  <property name="text">
+                   <string/>
+                  </property>
+                 </widget>
+                </item>
+                <item row="1" column="0">
+                 <widget class="QLabel" name="label_16">
+                  <property name="text">
+                   <string>Axis:</string>
+                  </property>
+                 </widget>
+                </item>
+                <item row="1" column="1">
+                 <widget class="ColorPickerButton" name="GeneralGraphAxis">
+                  <property name="text">
+                   <string/>
+                  </property>
+                 </widget>
+                </item>
+                <item row="2" column="0">
+                 <widget class="QLabel" name="label_17">
+                  <property name="text">
+                   <string>Divisions:</string>
+                  </property>
+                 </widget>
+                </item>
+                <item row="2" column="1">
+                 <widget class="ColorPickerButton" name="GeneralGraphDivisions">
+                  <property name="text">
+                   <string/>
+                  </property>
+                 </widget>
+                </item>
+               </layout>
+              </widget>
+             </item>
+             <item>
+              <spacer name="verticalSpacer_3">
+               <property name="orientation">
+                <enum>Qt::Vertical</enum>
+               </property>
+               <property name="sizeHint" stdset="0">
+                <size>
+                 <width>20</width>
+                 <height>40</height>
+                </size>
+               </property>
+              </spacer>
+             </item>
+            </layout>
+           </item>
+           <item>
+            <spacer name="horizontalSpacer_3">
+             <property name="orientation">
+              <enum>Qt::Horizontal</enum>
+             </property>
+             <property name="sizeHint" stdset="0">
+              <size>
+               <width>40</width>
+               <height>20</height>
+              </size>
+             </property>
+            </spacer>
+           </item>
+          </layout>
+         </item>
+        </layout>
+       </widget>
       </widget>
      </item>
     </layout>
@@ -474,6 +568,11 @@
    <extends>QLineEdit</extends>
    <header>CustomWidgets/siunitedit.h</header>
   </customwidget>
+  <customwidget>
+   <class>ColorPickerButton</class>
+   <extends>QPushButton</extends>
+   <header>CustomWidgets/colorpickerbutton.h</header>
+  </customwidget>
  </customwidgets>
  <resources/>
  <connections/>