diff --git a/doc/img/APTDemod_plugin.png b/doc/img/APTDemod_plugin.png
index 24d98125b..573fb0dc7 100644
Binary files a/doc/img/APTDemod_plugin.png and b/doc/img/APTDemod_plugin.png differ
diff --git a/doc/img/APTDemod_plugin_settings.png b/doc/img/APTDemod_plugin_settings.png
index 5934b4e54..fed33a7cf 100644
Binary files a/doc/img/APTDemod_plugin_settings.png and b/doc/img/APTDemod_plugin_settings.png differ
diff --git a/doc/img/RadioClock_waveforms.png b/doc/img/RadioClock_waveforms.png
new file mode 100644
index 000000000..365890455
Binary files /dev/null and b/doc/img/RadioClock_waveforms.png differ
diff --git a/plugins/channelrx/demodapt/aptdemod.cpp b/plugins/channelrx/demodapt/aptdemod.cpp
index 11c99bb1b..4fbe8fec6 100644
--- a/plugins/channelrx/demodapt/aptdemod.cpp
+++ b/plugins/channelrx/demodapt/aptdemod.cpp
@@ -584,6 +584,7 @@ int APTDemod::webapiActionsPost(
         {
             SWGSDRangel::SWGAPTDemodActions_aos* aos = swgAPTDemodActions->getAos();
             QString *satelliteName = aos->getSatelliteName();
+            qDebug() << "APTDemod::webapiActionsPost - AOS " << *satelliteName;
             if (satelliteName != nullptr)
             {
                 if (matchSatellite(*satelliteName))
@@ -617,6 +618,7 @@ int APTDemod::webapiActionsPost(
         {
             SWGSDRangel::SWGAPTDemodActions_los* los = swgAPTDemodActions->getLos();
             QString *satelliteName = los->getSatelliteName();
+            qDebug() << "APTDemod::webapiActionsPost - LOS " << *satelliteName;
 
             if (satelliteName != nullptr)
             {
diff --git a/plugins/channelrx/demodapt/aptdemodgui.cpp b/plugins/channelrx/demodapt/aptdemodgui.cpp
index fcbc9c175..163332c61 100644
--- a/plugins/channelrx/demodapt/aptdemodgui.cpp
+++ b/plugins/channelrx/demodapt/aptdemodgui.cpp
@@ -25,9 +25,10 @@
 #include <QAction>
 #include <QRegExp>
 #include <QFileDialog>
+#include <QGraphicsScene>
+#include <QGraphicsPixmapItem>
 
 #include "aptdemodgui.h"
-#include "util/ax25.h"
 
 #include "device/deviceuiset.h"
 #include "dsp/dspengine.h"
@@ -42,6 +43,7 @@
 #include "gui/devicestreamselectiondialog.h"
 #include "dsp/dspengine.h"
 #include "gui/crightclickenabler.h"
+#include "gui/graphicsviewzoom.h"
 #include "channel/channelwebapiutils.h"
 #include "maincore.h"
 
@@ -101,7 +103,20 @@ bool APTDemodGUI::handleMessage(const Message& message)
         const APTDemod::MsgImage& imageMsg = (APTDemod::MsgImage&) message;
         m_image = imageMsg.getImage();
         m_pixmap.convertFromImage(m_image);
-        ui->image->setPixmap(m_pixmap);
+        if (m_pixmapItem != nullptr)
+        {
+            m_pixmapItem->setPixmap(m_pixmap);
+            if (ui->zoomAll->isChecked()) {
+                ui->image->fitInView(m_pixmapItem, Qt::KeepAspectRatio);
+            }
+        }
+        else
+        {
+            m_pixmapItem = m_scene->addPixmap(m_pixmap);
+            m_pixmapItem->setPos(0, 0);
+            ui->image->fitInView(m_pixmapItem, Qt::KeepAspectRatio);
+        }
+
         QStringList imageTypes = imageMsg.getImageTypes();
         if (imageTypes.size() == 0)
         {
@@ -171,7 +186,19 @@ bool APTDemodGUI::handleMessage(const Message& message)
         }
 
         m_pixmap.convertFromImage(m_image);
-        ui->image->setPixmap(m_pixmap);
+        if (m_pixmapItem != nullptr)
+        {
+            m_pixmapItem->setPixmap(m_pixmap);
+            if (ui->zoomAll->isChecked()) {
+                ui->image->fitInView(m_pixmapItem, Qt::KeepAspectRatio);
+            }
+        }
+        else
+        {
+            m_pixmapItem = m_scene->addPixmap(m_pixmap);
+            m_pixmapItem->setPos(0, 0);
+            ui->image->fitInView(m_pixmapItem, Qt::KeepAspectRatio);
+        }
 
         return true;
     }
@@ -302,7 +329,9 @@ void APTDemodGUI::on_startStop_clicked(bool checked)
 
 void APTDemodGUI::on_resetDecoder_clicked()
 {
-    ui->image->setPixmap(QPixmap());
+    if (m_pixmapItem != nullptr) {
+        m_pixmapItem->setPixmap(QPixmap());
+    }
     ui->imageContainer->setWindowTitle("Received image");
     // Send message to reset decoder
     m_aptDemod->getInputMessageQueue()->push(APTDemod::MsgResetDecoder::create());
@@ -332,6 +361,30 @@ void APTDemodGUI::on_saveImage_clicked()
     }
 }
 
+void APTDemodGUI::on_zoomIn_clicked()
+{
+    m_zoom->gentleZoom(1.25);
+    ui->zoomAll->setChecked(false);
+}
+
+void APTDemodGUI::on_zoomOut_clicked()
+{
+    m_zoom->gentleZoom(0.75);
+    ui->zoomAll->setChecked(false);
+}
+
+void APTDemodGUI::on_zoomAll_clicked(bool checked)
+{
+    if (checked && (m_pixmapItem != nullptr)) {
+        ui->image->fitInView(m_pixmapItem, Qt::KeepAspectRatio);
+    }
+}
+
+void APTDemodGUI::on_image_zoomed()
+{
+    ui->zoomAll->setChecked(false);
+}
+
 void APTDemodGUI::onWidgetRolled(QWidget* widget, bool rollDown)
 {
     (void) widget;
@@ -389,7 +442,9 @@ APTDemodGUI::APTDemodGUI(PluginAPI* pluginAPI, DeviceUISet *deviceUISet, Baseban
     m_deviceUISet(deviceUISet),
     m_channelMarker(this),
     m_doApplySettings(true),
-    m_tickCount(0)
+    m_tickCount(0),
+    m_scene(nullptr),
+    m_pixmapItem(nullptr)
 {
     ui->setupUi(this);
 
@@ -425,6 +480,13 @@ APTDemodGUI::APTDemodGUI(PluginAPI* pluginAPI, DeviceUISet *deviceUISet, Baseban
     connect(&m_channelMarker, SIGNAL(highlightedByCursor()), this, SLOT(channelMarkerHighlightedByCursor()));
     connect(getInputMessageQueue(), SIGNAL(messageEnqueued()), this, SLOT(handleInputMessages()));
 
+    m_zoom = new GraphicsViewZoom(ui->image); // Deleted automatically when view is deleted
+    connect(m_zoom, SIGNAL(zoomed()), this, SLOT(on_image_zoomed()));
+
+    m_scene = new QGraphicsScene(ui->image);
+    ui->image->setScene(m_scene);
+    ui->image->show();
+
     displaySettings();
     applySettings(true);
 }
diff --git a/plugins/channelrx/demodapt/aptdemodgui.h b/plugins/channelrx/demodapt/aptdemodgui.h
index 7c324af48..b80c35f8d 100644
--- a/plugins/channelrx/demodapt/aptdemodgui.h
+++ b/plugins/channelrx/demodapt/aptdemodgui.h
@@ -42,6 +42,9 @@ class DeviceUISet;
 class BasebandSampleSink;
 class APTDemod;
 class APTDemodGUI;
+class QGraphicsScene;
+class QGraphicsPixmapItem;
+class GraphicsViewZoom;
 
 namespace Ui {
     class APTDemodGUI;
@@ -79,6 +82,9 @@ private:
 
     QImage m_image;
     QPixmap m_pixmap;
+    QGraphicsScene* m_scene;
+    QGraphicsPixmapItem* m_pixmapItem;
+    GraphicsViewZoom* m_zoom;
 
     explicit APTDemodGUI(PluginAPI* pluginAPI, DeviceUISet *deviceUISet, BasebandSampleSink *rxChannel, QWidget* parent = 0);
     virtual ~APTDemodGUI();
@@ -107,6 +113,10 @@ private slots:
     void on_showSettings_clicked();
     void on_resetDecoder_clicked();
     void on_saveImage_clicked();
+    void on_zoomIn_clicked();
+    void on_zoomOut_clicked();
+    void on_zoomAll_clicked(bool checked=false);
+    void on_image_zoomed();
     void onWidgetRolled(QWidget* widget, bool rollDown);
     void onMenuDialogCalled(const QPoint& p);
     void handleInputMessages();
diff --git a/plugins/channelrx/demodapt/aptdemodgui.ui b/plugins/channelrx/demodapt/aptdemodgui.ui
index 2579d8c26..d7eb1f9fc 100644
--- a/plugins/channelrx/demodapt/aptdemodgui.ui
+++ b/plugins/channelrx/demodapt/aptdemodgui.ui
@@ -356,6 +356,9 @@
     </item>
     <item>
      <layout class="QHBoxLayout" name="buttonLayout">
+      <property name="spacing">
+       <number>4</number>
+      </property>
       <item>
        <widget class="ButtonSwitch" name="startStop">
         <property name="toolTip">
@@ -372,7 +375,7 @@
        </widget>
       </item>
       <item>
-       <widget class="QPushButton" name="showSettings">
+       <widget class="QToolButton" name="showSettings">
         <property name="toolTip">
          <string>Show settings dialog</string>
         </property>
@@ -386,7 +389,7 @@
        </widget>
       </item>
       <item>
-       <widget class="QPushButton" name="resetDecoder">
+       <widget class="QToolButton" name="resetDecoder">
         <property name="toolTip">
          <string>Reset decoder (clears current image)</string>
         </property>
@@ -400,7 +403,7 @@
        </widget>
       </item>
       <item>
-       <widget class="QPushButton" name="saveImage">
+       <widget class="QToolButton" name="saveImage">
         <property name="toolTip">
          <string>Save image to disk</string>
         </property>
@@ -413,6 +416,54 @@
         </property>
        </widget>
       </item>
+      <item>
+       <widget class="QToolButton" name="zoomIn">
+        <property name="toolTip">
+         <string>Zoom in to image</string>
+        </property>
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../sdrgui/resources/res.qrc">
+          <normaloff>:/zoomin.png</normaloff>:/zoomin.png</iconset>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QToolButton" name="zoomOut">
+        <property name="toolTip">
+         <string>Zoom out from image</string>
+        </property>
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../sdrgui/resources/res.qrc">
+          <normaloff>:/zoomout.png</normaloff>:/zoomout.png</iconset>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="ButtonSwitch" name="zoomAll">
+        <property name="toolTip">
+         <string>Zoom image to fit window</string>
+        </property>
+        <property name="text">
+         <string>^</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../sdrgui/resources/res.qrc">
+          <normaloff>:/zoomall.png</normaloff>:/zoomall.png</iconset>
+        </property>
+        <property name="checkable">
+         <bool>true</bool>
+        </property>
+        <property name="checked">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
       <item>
        <spacer name="horizontalSpacer_3">
         <property name="orientation">
@@ -426,13 +477,6 @@
         </property>
        </spacer>
       </item>
-      <item>
-       <widget class="QLabel" name="channelsLabel">
-        <property name="text">
-         <string>Channels</string>
-        </property>
-       </widget>
-      </item>
       <item>
        <widget class="QComboBox" name="channels">
         <property name="minimumSize">
@@ -645,25 +689,13 @@
      </layout>
     </item>
     <item>
-     <widget class="ScaledImage" name="image">
-      <property name="sizePolicy">
-       <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
-        <horstretch>0</horstretch>
-        <verstretch>0</verstretch>
-       </sizepolicy>
-      </property>
+     <widget class="QGraphicsView" name="image">
       <property name="minimumSize">
        <size>
         <width>300</width>
         <height>350</height>
        </size>
       </property>
-      <property name="text">
-       <string/>
-      </property>
-      <property name="alignment">
-       <set>Qt::AlignCenter</set>
-      </property>
      </widget>
     </item>
    </layout>
@@ -677,9 +709,10 @@
    <container>1</container>
   </customwidget>
   <customwidget>
-   <class>ButtonSwitch</class>
-   <extends>QToolButton</extends>
-   <header>gui/buttonswitch.h</header>
+   <class>ValueDialZ</class>
+   <extends>QWidget</extends>
+   <header>gui/valuedialz.h</header>
+   <container>1</container>
   </customwidget>
   <customwidget>
    <class>LevelMeterSignalDB</class>
@@ -688,15 +721,9 @@
    <container>1</container>
   </customwidget>
   <customwidget>
-   <class>ValueDialZ</class>
-   <extends>QWidget</extends>
-   <header>gui/valuedialz.h</header>
-   <container>1</container>
-  </customwidget>
-  <customwidget>
-   <class>ScaledImage</class>
-   <extends>QLabel</extends>
-   <header>gui/scaledimage.h</header>
+   <class>ButtonSwitch</class>
+   <extends>QToolButton</extends>
+   <header>gui/buttonswitch.h</header>
   </customwidget>
  </customwidgets>
  <tabstops>
diff --git a/sdrgui/resources/res.qrc b/sdrgui/resources/res.qrc
index c426baebb..f62409640 100644
--- a/sdrgui/resources/res.qrc
+++ b/sdrgui/resources/res.qrc
@@ -107,6 +107,7 @@
     <file>load.png</file>
     <file>keyboard.png</file>
     <file>kill.png</file>
+    <file>zoomall.png</file>
     <file>zoomin.png</file>
     <file>zoomout.png</file>
     <file>LiberationMono-Regular.ttf</file>
diff --git a/sdrgui/resources/zoomall.png b/sdrgui/resources/zoomall.png
new file mode 100644
index 000000000..574cdcdf2
Binary files /dev/null and b/sdrgui/resources/zoomall.png differ