diff --git a/@MyDaq/MyDaq.mlapp b/@MyDaq/MyDaq.mlapp
index bb29741..c10bd53 100644
Binary files a/@MyDaq/MyDaq.mlapp and b/@MyDaq/MyDaq.mlapp differ
diff --git a/Test tools/Dummy objects/@MyDummyInstrument/MyDummyInstrument.m b/Test tools/Dummy objects/@MyDummyInstrument/MyDummyInstrument.m
index 5710fb8..209d5cc 100644
--- a/Test tools/Dummy objects/@MyDummyInstrument/MyDummyInstrument.m	
+++ b/Test tools/Dummy objects/@MyDummyInstrument/MyDummyInstrument.m	
@@ -1,61 +1,101 @@
 % Object for testing data acquisition and header collection functionality
 
 classdef MyDummyInstrument < MyInstrument & MyDataSource
     
-    properties (Access = public)
+    properties (Access = public, SetObservable = true)
         point_no = 1000
+        
+        trace_type = 'zero'
     end
     
     methods (Access = public)
         function this = MyDummyInstrument()
             createCommandList(this);
         end
         
         function readTrace(this)
             
             % Generate a random trace with the length equal to point_no
-            this.Trace.x = 1:this.point_no;
+            this.Trace.x = (0:this.point_no-1)/(this.point_no-1);
             this.Trace.y = rand(1, this.point_no);
             
+            switch this.trace_type
+                case 'zero'
+                    
+                    % Do nothing
+                case 'exp'
+                    
+                    % Add exponential "signal"
+                    a = 5+rand();
+                    b = 10*rand();
+                    
+                    sig = a*exp(-b*this.Trace.x);
+                    
+                    this.Trace.y = this.Trace.y + sig;
+                case 'lorentz'
+                    
+                    % Add lorentzian "signal"
+                    a = 10+rand();
+                    b = 10*rand();
+                    x0 = rand();
+                    dx = 0.05*rand();
+                    
+                    sig = a-b*dx^2./((this.Trace.x-x0).^2+dx^2);
+                    
+                    this.Trace.y = this.Trace.y + sig(:);
+                otherwise
+                    error(['Unsupported trace type ' this.trace_type])
+            end
+            
             triggerNewData(this);
         end
         
         function Lg = createLogger(this, varargin)
             function x = getRandomMeasurement()
                 sync(this);
                 x = this.cmd3;
             end
 
             Lg = MyLogger(varargin{:}, 'MeasFcn', @getRandomMeasurement);
             
             Lg.Record.data_headers = {'random 1', 'random 2', ...
                 'random 3', 'random 4', 'random 5'};
         end
         
         function idn(this)
             this.idn_str = 'dummy';
         end
     end
     
     methods (Access = protected)
         function createCommandList(this)
             
             % cmd1 is read and write accessible, it represents a paramter
             % which we can set and which does not change unless we set it
             addCommand(this, 'cmd1', ...
                 'readFcn',  @()this.cmd1, ...
                 'writeFcn', @(x)fprintf('cmd 1 write %e\n', x), ...
                 'default',  rand());
             
             addCommand(this, 'cmd2', ...
                 'readFcn',  @()rand(), ...
                 'info',     'read only scalar');
             
             % cmd3 is a read only vector
             addCommand(this, 'cmd3', ...
                 'readFcn',  @()rand(1,5), ...
                 'info',     'read only vector');
         end
     end
+    
+    methods 
+        function set.trace_type(this, val)
+            assert(strcmpi(val, 'zero')|| ...
+                strcmpi(val, 'exp')|| ...
+                strcmpi(val, 'lorentz'), ...
+                'Trace type must be ''zero'', ''exp'' or ''lorentz''.')
+            this.trace_type = lower(val);
+        end
+    end
 end
 
diff --git a/Test tools/Dummy objects/GuiDummyInstrument.mlapp b/Test tools/Dummy objects/GuiDummyInstrument.mlapp
index 3fcb91e..b998dd9 100644
Binary files a/Test tools/Dummy objects/GuiDummyInstrument.mlapp and b/Test tools/Dummy objects/GuiDummyInstrument.mlapp differ