diff --git a/invesalius/data/coordinates.py b/invesalius/data/coordinates.py
index 4635634..f9ab489 100644
--- a/invesalius/data/coordinates.py
+++ b/invesalius/data/coordinates.py
@@ -51,7 +51,7 @@ def GetCoordinates(trck_init, trck_id, ref_mode):
 
 def ClaronCoord(trck_init, trck_id, ref_mode):
     trck = trck_init[0]
-    scale = 10. * np.array([1., 1.0, -1.0])
+    scale = np.array([1.0, 1.0, -1.0])
     coord = None
     k = 0
     # TODO: try to replace while and use some Claron internal computation
diff --git a/invesalius/data/trackers.py b/invesalius/data/trackers.py
index 2496ded..6cef8f0 100644
--- a/invesalius/data/trackers.py
+++ b/invesalius/data/trackers.py
@@ -123,6 +123,8 @@ def PlhWrapperConnection():
         if trck_check:
             # First run is necessary to discard the first coord collection
             trck_init.Run()
+        else:
+            trck_init = trck_check
     except:
         print 'Could not connect to Polhemus via wrapper.'
 
@@ -195,6 +197,8 @@ def DisconnectTracker(tracker_id):
 
     :param tracker_id: ID of tracking device.
     """
+    from wx.lib.pubsub import pub as Publisher
+    Publisher.sendMessage('Update status text in GUI', _("Disconnecting tracker ..."))
     trck_init = None
     # TODO: create individual functions to disconnect each other device, e.g. Polhemus.
     if tracker_id == 1:
@@ -202,6 +206,7 @@ def DisconnectTracker(tracker_id):
             import pyclaron
             pyclaron.pyclaron().Close()
             lib_mode = 'wrapper'
+            print 'Claron tracker disconnected.'
         except ImportError:
             lib_mode = 'error'
             print 'The ClaronTracker library is not installed.'
@@ -211,6 +216,7 @@ def DisconnectTracker(tracker_id):
             import polhemus
             polhemus.polhemus().Close()
             lib_mode = 'wrapper'
+            print 'Polhemus tracker disconnected.'
         except ImportError:
             lib_mode = 'error'
             print 'The polhemus library is not installed.'
@@ -219,4 +225,6 @@ def DisconnectTracker(tracker_id):
         print 'Debug tracker disconnected.'
         lib_mode = 'debug'
 
+    Publisher.sendMessage('Update status text in GUI', _("Ready"))
+
     return trck_init, lib_mode
\ No newline at end of file
diff --git a/invesalius/gui/frame.py b/invesalius/gui/frame.py
index 791971e..7f3e0b1 100644
--- a/invesalius/gui/frame.py
+++ b/invesalius/gui/frame.py
@@ -382,6 +382,7 @@ class Frame(wx.Frame):
         Close all project data.
         """
         Publisher.sendMessage('Close Project')
+        Publisher.sendMessage('Disconnect tracker')
         s = ses.Session()
         if not s.IsOpen() or not s.project_path:
             Publisher.sendMessage('Exit')
diff --git a/invesalius/gui/task_navigator.py b/invesalius/gui/task_navigator.py
index d84c151..c0ca456 100644
--- a/invesalius/gui/task_navigator.py
+++ b/invesalius/gui/task_navigator.py
@@ -312,6 +312,7 @@ class NeuronavigationPanel(wx.Panel):
         Publisher.subscribe(self.LoadImageFiducials, 'Load image fiducials')
         Publisher.subscribe(self.UpdateTriggerState, 'Update trigger state')
         Publisher.subscribe(self.UpdateImageCoordinates, 'Set ball reference position')
+        Publisher.subscribe(self.OnDisconnectTracker, 'Disconnect tracker')
 
     def LoadImageFiducials(self, pubsub_evt):
         marker_id = pubsub_evt.data[0]
@@ -341,6 +342,10 @@ class NeuronavigationPanel(wx.Panel):
     def UpdateTriggerState (self, pubsub_evt):
         self.trigger_state = pubsub_evt.data
 
+    def OnDisconnectTracker(self, pubsub_evt):
+        if self.tracker_id:
+            dt.TrackerConnection(self.tracker_id, 'disconnect')
+
     def OnChoiceTracker(self, evt, ctrl):
         Publisher.sendMessage('Update status text in GUI', _("Configuring tracker ..."))
         if evt:
--
libgit2 0.21.2