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diff --git a/openEMS/python/Tutorials/MSL_NotchFilter.py b/openEMS/python/Tutorials/MSL_NotchFilter.py
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+++ b/openEMS/python/Tutorials/MSL_NotchFilter.py
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+# -*- coding: utf-8 -*-
+"""
+ Microstrip Notch Filter Tutorial
+
+ Describtion at:
+ http://openems.de/doc/openEMS/Tutorials.html#microstrip-notch-filter
+
+ Tested with
+  - python 3.4
+  - openEMS v0.0.34+
+
+ (C) 2016 Thorsten Liebig <thorsten.liebig@gmx.de>
+
+"""
+
+### Import Libraries
+import os, tempfile
+from pylab import *
+
+from CSXCAD  import ContinuousStructure
+from openEMS import openEMS
+from openEMS.physical_constants import *
+
+
+### Setup the simulation
+Sim_Path = os.path.join(tempfile.gettempdir(), 'NotchFilter')
+post_proc_only = False
+
+unit = 1e-6 # specify everything in um
+MSL_length = 50000
+MSL_width = 600
+substrate_thickness = 254
+substrate_epr = 3.66
+stub_length = 12e3
+f_max = 7e9
+
+### Setup FDTD parameters & excitation function
+FDTD = openEMS()
+FDTD.SetGaussExcite( f_max/2, f_max/2 )
+FDTD.SetBoundaryCond( ['PML_8', 'PML_8', 'MUR', 'MUR', 'PEC', 'MUR'] )
+
+### Setup Geometry & Mesh
+CSX = ContinuousStructure()
+FDTD.SetCSX(CSX)
+mesh = CSX.GetGrid()
+mesh.SetDeltaUnit(unit)
+
+resolution = C0/(f_max*sqrt(substrate_epr))/unit/50 # resolution of lambda/50
+third_mesh = array([2*resolution/3, -resolution/3])/4
+
+## Do manual meshing
+mesh.AddLine('x', 0)
+mesh.AddLine('x',  MSL_width/2+third_mesh)
+mesh.AddLine('x', -MSL_width/2-third_mesh)
+mesh.SmoothMeshLines('x', resolution/4)
+
+mesh.AddLine('x', [-MSL_length, MSL_length])
+mesh.SmoothMeshLines('x', resolution)
+
+mesh.AddLine('y', 0)
+mesh.AddLine('y',  MSL_width/2+third_mesh)
+mesh.AddLine('y', -MSL_width/2-third_mesh)
+mesh.SmoothMeshLines('y', resolution/4)
+
+mesh.AddLine('y', [-15*MSL_width, 15*MSL_width+stub_length])
+mesh.AddLine('y', (MSL_width/2+stub_length)+third_mesh)
+mesh.SmoothMeshLines('y', resolution)
+
+mesh.AddLine('z', linspace(0,substrate_thickness,5))
+mesh.AddLine('z', 3000)
+mesh.SmoothMeshLines('z', resolution)
+
+## Add the substrate
+substrate = CSX.AddMaterial( 'RO4350B', epsilon=substrate_epr)
+start = [-MSL_length, -15*MSL_width, 0]
+stop  = [+MSL_length, +15*MSL_width+stub_length, substrate_thickness]
+substrate.AddBox(start, stop )
+
+## MSL port setup
+port = [None, None]
+pec = CSX.AddMetal( 'PEC' )
+portstart = [ -MSL_length, -MSL_width/2, substrate_thickness]
+portstop  = [ 0,  MSL_width/2, 0]
+port[0] = FDTD.AddMSLPort( 1,  pec, portstart, portstop, 'x', 'z', excite=-1, FeedShift=10*resolution, MeasPlaneShift=MSL_length/3, priority=10)
+
+portstart = [MSL_length, -MSL_width/2, substrate_thickness]
+portstop  = [0         ,  MSL_width/2, 0]
+port[1] = FDTD.AddMSLPort( 2, pec, portstart, portstop, 'x', 'z', MeasPlaneShift=MSL_length/3, priority=10 )
+
+## Filter-Stub Definition
+start = [-MSL_width/2,  MSL_width/2, substrate_thickness]
+stop  = [ MSL_width/2,  MSL_width/2+stub_length, substrate_thickness]
+pec.AddBox(start, stop, priority=10 )
+
+### Run the simulation
+if 0:  # debugging only
+    CSX_file = os.path.join(Sim_Path, 'notch.xml')
+    if not os.path.exists(Sim_Path):
+        os.mkdir(Sim_Path)
+    CSX.Write2XML(CSX_file)
+    os.system(r'AppCSXCAD "{}"'.format(CSX_file))
+
+
+if not post_proc_only:
+    FDTD.Run(Sim_Path, verbose=3, cleanup=True)
+
+### Post-processing and plotting
+f = linspace( 1e6, f_max, 1601 )
+for p in port:
+    p.CalcPort( Sim_Path, f, ref_impedance = 50)
+
+s11 = port[0].uf_ref / port[0].uf_inc
+s21 = port[1].uf_ref / port[0].uf_inc
+
+plot(f/1e9,20*log10(abs(s11)),'k-',linewidth=2 , label='$S_{11}$')
+grid()
+plot(f/1e9,20*log10(abs(s21)),'r--',linewidth=2 , label='$S_{21}$')
+legend()
+ylabel('S-Parameter (dB)')
+xlabel('frequency (GHz)')
+ylim([-40, 2])
+
+show()