Merge branch 'next' into digital

Conflicts:
	gnuradio-core/src/lib/filter/gr_pfb_clock_sync_ccf.h
	gnuradio-core/src/lib/general/general.i
	gnuradio-core/src/lib/general/gr_pll_carriertracking_cc.cc
	gnuradio-core/src/lib/general/gr_pll_freqdet_cf.cc
	gnuradio-core/src/lib/general/gr_pll_refout_cc.cc
	gnuradio-core/src/python/gnuradio/gr/qa_pll_carriertracking.py
	gnuradio-core/src/python/gnuradio/gr/qa_pll_freqdet.py
	gnuradio-core/src/python/gnuradio/gr/qa_pll_refout.py

20 files changed, 4100 insertions, 393 deletions

diff --git a/gnuradio-examples/grc/trellis/interference_cancellation.grc b/gnuradio-examples/grc/trellis/interference_cancellation.grc
index e93babd78..7674b4bf1 100644
--- a/gnuradio-examples/grc/trellis/interference_cancellation.grc
+++ b/gnuradio-examples/grc/trellis/interference_cancellation.grc
@@ -1,6 +1,6 @@
 <?xml version='1.0' encoding='ASCII'?>
 <flow_graph>
-  <timestamp>Thu Mar 19 11:22:40 2009</timestamp>
+  <timestamp>Wed Aug 31 17:40:25 2011</timestamp>
   <block>
     <key>options</key>
     <param>
@@ -36,6 +36,14 @@
       <value>Custom</value>
     </param>
     <param>
+      <key>run_options</key>
+      <value>prompt</value>
+    </param>
+    <param>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
       <key>realtime_scheduling</key>
       <value></value>
     </param>
@@ -79,18 +87,22 @@
       <value>100</value>
     </param>
     <param>
-      <key>slider_length</key>
-      <value>200</value>
+      <key>style</key>
+      <value>wx.SL_HORIZONTAL</value>
     </param>
     <param>
-      <key>slider_type</key>
-      <value>horizontal</value>
+      <key>converver</key>
+      <value>float_converter</value>
     </param>
     <param>
       <key>grid_pos</key>
       <value></value>
     </param>
     <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
       <key>_coordinate</key>
       <value>(243, 11)</value>
     </param>
@@ -130,18 +142,22 @@
       <value>100</value>
     </param>
     <param>
-      <key>slider_length</key>
-      <value>200</value>
+      <key>style</key>
+      <value>wx.SL_HORIZONTAL</value>
     </param>
     <param>
-      <key>slider_type</key>
-      <value>horizontal</value>
+      <key>converver</key>
+      <value>float_converter</value>
     </param>
     <param>
       <key>grid_pos</key>
       <value></value>
     </param>
     <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
       <key>_coordinate</key>
       <value>(447, 14)</value>
     </param>
@@ -213,41 +229,6 @@
     </param>
   </block>
   <block>
-    <key>gr_chunks_to_symbols_xx</key>
-    <param>
-      <key>id</key>
-      <value>gr_chunks_to_symbols_xx_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>in_type</key>
-      <value>short</value>
-    </param>
-    <param>
-      <key>out_type</key>
-      <value>complex</value>
-    </param>
-    <param>
-      <key>symbol_table</key>
-      <value>1,1j,-1j,-1</value>
-    </param>
-    <param>
-      <key>dimension</key>
-      <value>1</value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(665, 187)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
-  <block>
     <key>gr_multiply_const_vxx</key>
     <param>
       <key>id</key>
@@ -344,6 +325,10 @@
       <value>1</value>
     </param>
     <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
       <key>_coordinate</key>
       <value>(660, 311)</value>
     </param>
@@ -638,6 +623,10 @@
       <value>1</value>
     </param>
     <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
       <key>_coordinate</key>
       <value>(405, 998)</value>
     </param>
@@ -816,6 +805,10 @@
       <value>1</value>
     </param>
     <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
       <key>_coordinate</key>
       <value>(420, 1368)</value>
     </param>
@@ -968,10 +961,10 @@
     </param>
   </block>
   <block>
-    <key>wxgui_numbersink2</key>
+    <key>trellis_encoder_xx</key>
     <param>
       <key>id</key>
-      <value>wxgui_numbersink2_2</value>
+      <value>trellis_encoder_xx_1</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -979,71 +972,74 @@
     </param>
     <param>
       <key>type</key>
-      <value>float</value>
+      <value>ss</value>
     </param>
     <param>
-      <key>title</key>
-      <value>BER 2 (raw)</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>units</key>
-      <value>BER</value>
+      <key>init_state</key>
+      <value>0</value>
     </param>
     <param>
-      <key>samp_rate</key>
-      <value>R</value>
+      <key>_coordinate</key>
+      <value>(336, 311)</value>
     </param>
     <param>
-      <key>base_value</key>
-      <value>0.0</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>trellis_viterbi_combined_xx</key>
     <param>
-      <key>min_value</key>
-      <value>0</value>
+      <key>id</key>
+      <value>trellis_viterbi_combined_xx_1</value>
     </param>
     <param>
-      <key>max_value</key>
-      <value>1.0</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>factor</key>
-      <value>1.0</value>
+      <key>type</key>
+      <value>c</value>
     </param>
     <param>
-      <key>decimal_places</key>
-      <value>6</value>
+      <key>out_type</key>
+      <value>s</value>
     </param>
     <param>
-      <key>ref_level</key>
-      <value>0</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>number_rate</key>
-      <value>15</value>
+      <key>block_size</key>
+      <value>1000</value>
     </param>
     <param>
-      <key>peak_hold</key>
-      <value>False</value>
+      <key>init_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>average</key>
-      <value>False</value>
+      <key>final_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>avg_alpha</key>
-      <value>0.001</value>
+      <key>dim</key>
+      <value>1</value>
     </param>
     <param>
-      <key>show_gauge</key>
-      <value>True</value>
+      <key>table</key>
+      <value>alpha**0.5*1,alpha**0.5*1j,alpha**0.5*(-1j),alpha**0.5*(-1)</value>
     </param>
     <param>
-      <key>grid_pos</key>
-      <value>0,1,1,1</value>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1260, 659)</value>
+      <value>(79, 501)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1051,10 +1047,10 @@
     </param>
   </block>
   <block>
-    <key>wxgui_numbersink2</key>
+    <key>trellis_viterbi_combined_xx</key>
     <param>
       <key>id</key>
-      <value>wxgui_numbersink2_3</value>
+      <value>trellis_viterbi_combined_xx_2</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1062,71 +1058,74 @@
     </param>
     <param>
       <key>type</key>
-      <value>float</value>
+      <value>c</value>
     </param>
     <param>
-      <key>title</key>
-      <value>BER 2 (after cancelling user 1)</value>
+      <key>out_type</key>
+      <value>s</value>
     </param>
     <param>
-      <key>units</key>
-      <value>BER</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>samp_rate</key>
-      <value>R</value>
+      <key>block_size</key>
+      <value>1000</value>
     </param>
     <param>
-      <key>base_value</key>
-      <value>0.0</value>
+      <key>init_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>min_value</key>
-      <value>0</value>
+      <key>final_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>max_value</key>
-      <value>1.0</value>
+      <key>dim</key>
+      <value>1</value>
     </param>
     <param>
-      <key>factor</key>
-      <value>1.0</value>
+      <key>table</key>
+      <value>(1-alpha)**0.5*1,(1-alpha)**0.5*1j,(1-alpha)**0.5*(-1j),(1-alpha)**0.5*(-1)</value>
     </param>
     <param>
-      <key>decimal_places</key>
-      <value>6</value>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
     </param>
     <param>
-      <key>ref_level</key>
-      <value>0</value>
+      <key>_coordinate</key>
+      <value>(82, 766)</value>
     </param>
     <param>
-      <key>number_rate</key>
-      <value>15</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>trellis_encoder_xx</key>
     <param>
-      <key>peak_hold</key>
-      <value>False</value>
+      <key>id</key>
+      <value>trellis_encoder_xx_2</value>
     </param>
     <param>
-      <key>average</key>
-      <value>False</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>avg_alpha</key>
-      <value>0.001</value>
+      <key>type</key>
+      <value>ss</value>
     </param>
     <param>
-      <key>show_gauge</key>
-      <value>True</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>grid_pos</key>
-      <value>1,1,1,1</value>
+      <key>init_state</key>
+      <value>0</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1262, 1020)</value>
+      <value>(89, 998)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1134,10 +1133,10 @@
     </param>
   </block>
   <block>
-    <key>wxgui_numbersink2</key>
+    <key>trellis_viterbi_combined_xx</key>
     <param>
       <key>id</key>
-      <value>wxgui_numbersink2_3_0</value>
+      <value>trellis_viterbi_combined_xx_0</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1145,71 +1144,74 @@
     </param>
     <param>
       <key>type</key>
-      <value>float</value>
+      <value>c</value>
     </param>
     <param>
-      <key>title</key>
-      <value>BER 1 (after cancelling user 2)</value>
+      <key>out_type</key>
+      <value>s</value>
     </param>
     <param>
-      <key>units</key>
-      <value>BER</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>samp_rate</key>
-      <value>R</value>
+      <key>block_size</key>
+      <value>1000</value>
     </param>
     <param>
-      <key>base_value</key>
-      <value>0.0</value>
+      <key>init_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>min_value</key>
-      <value>0</value>
+      <key>final_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>max_value</key>
-      <value>1.0</value>
+      <key>dim</key>
+      <value>1</value>
     </param>
     <param>
-      <key>factor</key>
-      <value>1.0</value>
+      <key>table</key>
+      <value>(1-alpha)**0.5*1,(1-alpha)**0.5*1j,(1-alpha)**0.5*(-1j),(1-alpha)**0.5*(-1)</value>
     </param>
     <param>
-      <key>decimal_places</key>
-      <value>6</value>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
     </param>
     <param>
-      <key>ref_level</key>
-      <value>0</value>
+      <key>_coordinate</key>
+      <value>(83, 1111)</value>
     </param>
     <param>
-      <key>number_rate</key>
-      <value>15</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>trellis_encoder_xx</key>
     <param>
-      <key>peak_hold</key>
-      <value>False</value>
+      <key>id</key>
+      <value>trellis_encoder_xx_2_0</value>
     </param>
     <param>
-      <key>average</key>
-      <value>False</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>avg_alpha</key>
-      <value>0.001</value>
+      <key>type</key>
+      <value>ss</value>
     </param>
     <param>
-      <key>show_gauge</key>
-      <value>True</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>grid_pos</key>
-      <value>1,0,1,1</value>
+      <key>init_state</key>
+      <value>0</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1269, 1417)</value>
+      <value>(105, 1367)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1217,53 +1219,54 @@
     </param>
   </block>
   <block>
-    <key>variable</key>
+    <key>trellis_viterbi_combined_xx</key>
     <param>
       <key>id</key>
-      <value>R</value>
+      <value>trellis_viterbi_combined_xx_0_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>value</key>
-      <value>10e3</value>
+      <key>type</key>
+      <value>c</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(748, 12)</value>
+      <key>out_type</key>
+      <value>s</value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
-  </block>
-  <block>
-    <key>trellis_encoder_xx</key>
     <param>
-      <key>id</key>
-      <value>trellis_encoder_xx_0</value>
+      <key>block_size</key>
+      <value>1000</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>init_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>type</key>
-      <value>ss</value>
+      <key>final_state</key>
+      <value>-1</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>dim</key>
+      <value>1</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>0</value>
+      <key>table</key>
+      <value>alpha**0.5*1,alpha**0.5*1j,alpha**0.5*(-1j),alpha**0.5*(-1)</value>
+    </param>
+    <param>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(334, 190)</value>
+      <value>(75, 1495)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1271,10 +1274,10 @@
     </param>
   </block>
   <block>
-    <key>trellis_encoder_xx</key>
+    <key>gr_add_xx</key>
     <param>
       <key>id</key>
-      <value>trellis_encoder_xx_1</value>
+      <value>gr_add_xx_1</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1282,19 +1285,19 @@
     </param>
     <param>
       <key>type</key>
-      <value>ss</value>
+      <value>complex</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>num_inputs</key>
+      <value>2</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>0</value>
+      <key>vlen</key>
+      <value>1</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(336, 311)</value>
+      <value>(1400, 262)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1302,10 +1305,10 @@
     </param>
   </block>
   <block>
-    <key>trellis_viterbi_combined_xx</key>
+    <key>wxgui_scopesink2</key>
     <param>
       <key>id</key>
-      <value>trellis_viterbi_combined_xx_1</value>
+      <value>wxgui_scopesink2_0</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1313,43 +1316,63 @@
     </param>
     <param>
       <key>type</key>
-      <value>c</value>
+      <value>complex</value>
     </param>
     <param>
-      <key>out_type</key>
-      <value>s</value>
+      <key>title</key>
+      <value>Scope Plot</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>samp_rate</key>
+      <value>R</value>
     </param>
     <param>
-      <key>block_size</key>
-      <value>1000</value>
+      <key>v_scale</key>
+      <value>0</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>-1</value>
+      <key>v_offset</key>
+      <value>0</value>
     </param>
     <param>
-      <key>final_state</key>
-      <value>-1</value>
+      <key>t_scale</key>
+      <value>0</value>
     </param>
     <param>
-      <key>dim</key>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
       <value>1</value>
     </param>
     <param>
-      <key>table</key>
-      <value>alpha**0.5*1,alpha**0.5*1j,alpha**0.5*(-1j),alpha**0.5*(-1)</value>
+      <key>win_size</key>
+      <value></value>
     </param>
     <param>
-      <key>metric_type</key>
-      <value>trellis.TRELLIS_EUCLIDEAN</value>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>trig_mode</key>
+      <value>gr.gr_TRIG_MODE_AUTO</value>
+    </param>
+    <param>
+      <key>y_axis_label</key>
+      <value>Counts</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(79, 501)</value>
+      <value>(1533, 149)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1357,54 +1380,53 @@
     </param>
   </block>
   <block>
-    <key>trellis_viterbi_combined_xx</key>
+    <key>variable</key>
     <param>
       <key>id</key>
-      <value>trellis_viterbi_combined_xx_2</value>
+      <value>prefix</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>type</key>
-      <value>c</value>
-    </param>
-    <param>
-      <key>out_type</key>
-      <value>s</value>
+      <key>value</key>
+      <value>"/n/harrisville/x/anastas/gnuradio_trunk/"</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>_coordinate</key>
+      <value>(871, 14)</value>
     </param>
     <param>
-      <key>block_size</key>
-      <value>1000</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>trellis_encoder_xx</key>
     <param>
-      <key>init_state</key>
-      <value>-1</value>
+      <key>id</key>
+      <value>trellis_encoder_xx_0</value>
     </param>
     <param>
-      <key>final_state</key>
-      <value>-1</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>dim</key>
-      <value>1</value>
+      <key>type</key>
+      <value>ss</value>
     </param>
     <param>
-      <key>table</key>
-      <value>(1-alpha)**0.5*1,(1-alpha)**0.5*1j,(1-alpha)**0.5*(-1j),(1-alpha)**0.5*(-1)</value>
+      <key>fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
     </param>
     <param>
-      <key>metric_type</key>
-      <value>trellis.TRELLIS_EUCLIDEAN</value>
+      <key>init_state</key>
+      <value>0</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(82, 766)</value>
+      <value>(340, 187)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1412,10 +1434,10 @@
     </param>
   </block>
   <block>
-    <key>trellis_encoder_xx</key>
+    <key>gr_throttle</key>
     <param>
       <key>id</key>
-      <value>trellis_encoder_xx_2</value>
+      <value>gr_throttle_0</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1423,19 +1445,19 @@
     </param>
     <param>
       <key>type</key>
-      <value>ss</value>
+      <value>short</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>samples_per_second</key>
+      <value>R</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>0</value>
+      <key>vlen</key>
+      <value>1</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(89, 998)</value>
+      <value>(534, 149)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1443,54 +1465,61 @@
     </param>
   </block>
   <block>
-    <key>trellis_viterbi_combined_xx</key>
+    <key>gr_chunks_to_symbols_xx</key>
     <param>
       <key>id</key>
-      <value>trellis_viterbi_combined_xx_0</value>
+      <value>gr_chunks_to_symbols_xx_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>type</key>
-      <value>c</value>
+      <key>in_type</key>
+      <value>short</value>
     </param>
     <param>
       <key>out_type</key>
-      <value>s</value>
+      <value>complex</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>symbol_table</key>
+      <value>1,1j,-1j,-1</value>
     </param>
     <param>
-      <key>block_size</key>
-      <value>1000</value>
+      <key>dimension</key>
+      <value>1</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>-1</value>
+      <key>num_ports</key>
+      <value>1</value>
     </param>
     <param>
-      <key>final_state</key>
-      <value>-1</value>
+      <key>_coordinate</key>
+      <value>(682, 186)</value>
     </param>
     <param>
-      <key>dim</key>
-      <value>1</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>variable</key>
     <param>
-      <key>table</key>
-      <value>(1-alpha)**0.5*1,(1-alpha)**0.5*1j,(1-alpha)**0.5*(-1j),(1-alpha)**0.5*(-1)</value>
+      <key>id</key>
+      <value>R</value>
     </param>
     <param>
-      <key>metric_type</key>
-      <value>trellis.TRELLIS_EUCLIDEAN</value>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>100e3</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(83, 1111)</value>
+      <value>(748, 12)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1498,10 +1527,10 @@
     </param>
   </block>
   <block>
-    <key>trellis_encoder_xx</key>
+    <key>wxgui_numbersink2</key>
     <param>
       <key>id</key>
-      <value>trellis_encoder_xx_2_0</value>
+      <value>wxgui_numbersink2_0</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1509,74 +1538,75 @@
     </param>
     <param>
       <key>type</key>
-      <value>ss</value>
+      <value>float</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>title</key>
+      <value>BER 1 (raw)</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>0</value>
+      <key>units</key>
+      <value>BER</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(105, 1367)</value>
+      <key>samp_rate</key>
+      <value>R</value>
     </param>
     <param>
-      <key>_rotation</key>
+      <key>min_value</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>trellis_viterbi_combined_xx</key>
     <param>
-      <key>id</key>
-      <value>trellis_viterbi_combined_xx_0_0</value>
+      <key>max_value</key>
+      <value>1</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>factor</key>
+      <value>1.0</value>
     </param>
     <param>
-      <key>type</key>
-      <value>c</value>
+      <key>decimal_places</key>
+      <value>6</value>
     </param>
     <param>
-      <key>out_type</key>
-      <value>s</value>
+      <key>ref_level</key>
+      <value>0</value>
     </param>
     <param>
-      <key>fsm_args</key>
-      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_16.fsm"</value>
+      <key>number_rate</key>
+      <value>15</value>
     </param>
     <param>
-      <key>block_size</key>
-      <value>1000</value>
+      <key>peak_hold</key>
+      <value>False</value>
     </param>
     <param>
-      <key>init_state</key>
-      <value>-1</value>
+      <key>average</key>
+      <value>True</value>
     </param>
     <param>
-      <key>final_state</key>
-      <value>-1</value>
+      <key>avg_alpha</key>
+      <value>0.001</value>
     </param>
     <param>
-      <key>dim</key>
-      <value>1</value>
+      <key>show_gauge</key>
+      <value>True</value>
     </param>
     <param>
-      <key>table</key>
-      <value>alpha**0.5*1,alpha**0.5*1j,alpha**0.5*(-1j),alpha**0.5*(-1)</value>
+      <key>win_size</key>
+      <value></value>
     </param>
     <param>
-      <key>metric_type</key>
-      <value>trellis.TRELLIS_EUCLIDEAN</value>
+      <key>grid_pos</key>
+      <value>0,0,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(75, 1495)</value>
+      <value>(1267, 410)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1584,53 +1614,86 @@
     </param>
   </block>
   <block>
-    <key>variable</key>
+    <key>wxgui_numbersink2</key>
     <param>
       <key>id</key>
-      <value>prefix</value>
+      <value>wxgui_numbersink2_2</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>value</key>
-      <value>"../../../"</value>
+      <key>type</key>
+      <value>float</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(871, 14)</value>
+      <key>title</key>
+      <value>BER 2 (raw)</value>
     </param>
     <param>
-      <key>_rotation</key>
+      <key>units</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>min_value</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>gr_add_xx</key>
     <param>
-      <key>id</key>
-      <value>gr_add_xx_1</value>
+      <key>max_value</key>
+      <value>1.0</value>
     </param>
     <param>
-      <key>_enabled</key>
+      <key>factor</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>decimal_places</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>number_rate</key>
+      <value>15</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
       <value>True</value>
     </param>
     <param>
-      <key>type</key>
-      <value>complex</value>
+      <key>avg_alpha</key>
+      <value>0.001</value>
     </param>
     <param>
-      <key>num_inputs</key>
-      <value>2</value>
+      <key>show_gauge</key>
+      <value>True</value>
     </param>
     <param>
-      <key>vlen</key>
-      <value>1</value>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>0,1,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1400, 262)</value>
+      <value>(1260, 659)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1641,7 +1704,7 @@
     <key>wxgui_numbersink2</key>
     <param>
       <key>id</key>
-      <value>wxgui_numbersink2_0</value>
+      <value>wxgui_numbersink2_3</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1653,7 +1716,7 @@
     </param>
     <param>
       <key>title</key>
-      <value>BER 1 (raw)</value>
+      <value>BER 2 (after cancelling user 1)</value>
     </param>
     <param>
       <key>units</key>
@@ -1664,16 +1727,12 @@
       <value>R</value>
     </param>
     <param>
-      <key>base_value</key>
-      <value>0.0</value>
-    </param>
-    <param>
       <key>min_value</key>
       <value>0</value>
     </param>
     <param>
       <key>max_value</key>
-      <value>1</value>
+      <value>1.0</value>
     </param>
     <param>
       <key>factor</key>
@@ -1697,7 +1756,7 @@
     </param>
     <param>
       <key>average</key>
-      <value>False</value>
+      <value>True</value>
     </param>
     <param>
       <key>avg_alpha</key>
@@ -1708,12 +1767,20 @@
       <value>True</value>
     </param>
     <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
       <key>grid_pos</key>
-      <value>0,0,1,1</value>
+      <value>1,1,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1267, 410)</value>
+      <value>(1262, 1020)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1721,10 +1788,10 @@
     </param>
   </block>
   <block>
-    <key>wxgui_scopesink2</key>
+    <key>wxgui_numbersink2</key>
     <param>
       <key>id</key>
-      <value>wxgui_scopesink2_0</value>
+      <value>wxgui_numbersink2_3_0</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -1732,43 +1799,75 @@
     </param>
     <param>
       <key>type</key>
-      <value>complex</value>
+      <value>float</value>
     </param>
     <param>
       <key>title</key>
-      <value>Scope Plot</value>
+      <value>BER 1 (after cancelling user 2)</value>
+    </param>
+    <param>
+      <key>units</key>
+      <value>BER</value>
     </param>
     <param>
       <key>samp_rate</key>
       <value>R</value>
     </param>
     <param>
-      <key>v_scale</key>
+      <key>min_value</key>
       <value>0</value>
     </param>
     <param>
-      <key>t_scale</key>
+      <key>max_value</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>factor</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>decimal_places</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>ref_level</key>
       <value>0</value>
     </param>
     <param>
-      <key>ac_couple</key>
+      <key>number_rate</key>
+      <value>15</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
       <value>False</value>
     </param>
     <param>
-      <key>xy_mode</key>
+      <key>average</key>
       <value>True</value>
     </param>
     <param>
-      <key>num_inputs</key>
-      <value>1</value>
+      <key>avg_alpha</key>
+      <value>0.001</value>
+    </param>
+    <param>
+      <key>show_gauge</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
     </param>
     <param>
       <key>grid_pos</key>
+      <value>1,0,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
       <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1533, 149)</value>
+      <value>(1269, 1417)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1782,12 +1881,6 @@
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>trellis_encoder_xx_0</source_block_id>
-    <sink_block_id>gr_chunks_to_symbols_xx_0</sink_block_id>
-    <source_key>0</source_key>
-    <sink_key>0</sink_key>
-  </connection>
-  <connection>
     <source_block_id>trellis_encoder_xx_1</source_block_id>
     <sink_block_id>gr_chunks_to_symbols_xx_1</sink_block_id>
     <source_key>0</source_key>
@@ -2069,4 +2162,16 @@
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
+  <connection>
+    <source_block_id>trellis_encoder_xx_0</source_block_id>
+    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_throttle_0</source_block_id>
+    <sink_block_id>gr_chunks_to_symbols_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
 </flow_graph>
diff --git a/gnuradio-examples/grc/trellis/pccc.grc b/gnuradio-examples/grc/trellis/pccc.grc
new file mode 100644
index 000000000..c3111c321
--- /dev/null
+++ b/gnuradio-examples/grc/trellis/pccc.grc
@@ -0,0 +1,832 @@
+<?xml version='1.0' encoding='ASCII'?>
+<flow_graph>
+  <timestamp>Thu Sep  1 12:53:13 2011</timestamp>
+  <block>
+    <key>options</key>
+    <param>
+      <key>id</key>
+      <value>sccc1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Serially Concatenated Convolutional Code</value>
+    </param>
+    <param>
+      <key>author</key>
+      <value>AA</value>
+    </param>
+    <param>
+      <key>description</key>
+      <value>gnuradio flow graph</value>
+    </param>
+    <param>
+      <key>window_size</key>
+      <value>2048, 2048</value>
+    </param>
+    <param>
+      <key>generate_options</key>
+      <value>wx_gui</value>
+    </param>
+    <param>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>run_options</key>
+      <value>prompt</value>
+    </param>
+    <param>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>realtime_scheduling</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(10, 10)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>10**(-snr_db/10)</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(389, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>prefix</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>"/n/harrisville/x/anastas/gnuradio_trunk/"</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(590, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(764, 16)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable_slider</key>
+    <param>
+      <key>id</key>
+      <value>snr_db</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>label</key>
+      <value>SNR (dB)</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>-10</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>num_steps</key>
+      <value>100</value>
+    </param>
+    <param>
+      <key>style</key>
+      <value>wx.SL_HORIZONTAL</value>
+    </param>
+    <param>
+      <key>converver</key>
+      <value>float_converter</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(229, 13)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_multiply_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_multiply_xx_2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(392, 591)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_short_to_float</key>
+    <param>
+      <key>id</key>
+      <value>gr_short_to_float_1_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(535, 609)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_numbersink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_numbersink2_3_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>units</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>min_value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max_value</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>factor</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>decimal_places</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>number_rate</key>
+      <value>15</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0.001</value>
+    </param>
+    <param>
+      <key>show_gauge</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1,0,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(713, 426)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_noise_source_x</key>
+    <param>
+      <key>id</key>
+      <value>gr_noise_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>noise_type</key>
+      <value>gr.GR_GAUSSIAN</value>
+    </param>
+    <param>
+      <key>amp</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>seed</key>
+      <value>42</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(672, 290)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_scopesink2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Scope Plot</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>v_offset</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>trig_mode</key>
+      <value>gr.gr_TRIG_MODE_AUTO</value>
+    </param>
+    <param>
+      <key>y_axis_label</key>
+      <value>Counts</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(952, 73)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>random_source_x</key>
+    <param>
+      <key>id</key>
+      <value>random_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_samps</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(21, 170)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_throttle</key>
+    <param>
+      <key>id</key>
+      <value>gr_throttle_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>samples_per_second</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(517, 103)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_chunks_to_symbols_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_chunks_to_symbols_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>in_type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>symbol_table</key>
+      <value>-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7,0,   0,-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7</value>
+    </param>
+    <param>
+      <key>dimension</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(551, 184)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_pccc_encoder_xx</key>
+    <param>
+      <key>id</key>
+      <value>trellis_pccc_encoder_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>ss</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>interleaver_args</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>bl</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(236, 147)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>100e3</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(482, 17)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_add_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_add_xx_1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(951, 256)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_pccc_decoder_combined_xx</key>
+    <param>
+      <key>id</key>
+      <value>trellis_pccc_decoder_combined_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>f</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>s</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>o_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>interleaver</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>block_size</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>iterations</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>dim</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>table</key>
+      <value>-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7,0,   0,-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7</value>
+    </param>
+    <param>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
+    </param>
+    <param>
+      <key>siso_type</key>
+      <value>trellis.TRELLIS_MIN_SUM</value>
+    </param>
+    <param>
+      <key>scaling</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(196, 274)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_sub_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_sub_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(217, 597)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_throttle_0</source_block_id>
+    <sink_block_id>gr_chunks_to_symbols_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>wxgui_scopesink2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_noise_source_x_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_chunks_to_symbols_xx_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_multiply_xx_2_0</source_block_id>
+    <sink_block_id>gr_short_to_float_1_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_short_to_float_1_0</source_block_id>
+    <sink_block_id>wxgui_numbersink2_3_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>trellis_pccc_encoder_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_pccc_encoder_xx_0</source_block_id>
+    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>trellis_pccc_decoder_combined_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_pccc_decoder_combined_xx_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+</flow_graph>
diff --git a/gnuradio-examples/grc/trellis/pccc1.grc b/gnuradio-examples/grc/trellis/pccc1.grc
new file mode 100644
index 000000000..15a63707e
--- /dev/null
+++ b/gnuradio-examples/grc/trellis/pccc1.grc
@@ -0,0 +1,857 @@
+<?xml version='1.0' encoding='ASCII'?>
+<flow_graph>
+  <timestamp>Wed Aug 31 20:34:39 2011</timestamp>
+  <block>
+    <key>options</key>
+    <param>
+      <key>id</key>
+      <value>sccc1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Serially Concatenated Convolutional Code</value>
+    </param>
+    <param>
+      <key>author</key>
+      <value>AA</value>
+    </param>
+    <param>
+      <key>description</key>
+      <value>gnuradio flow graph</value>
+    </param>
+    <param>
+      <key>window_size</key>
+      <value>2048, 2048</value>
+    </param>
+    <param>
+      <key>generate_options</key>
+      <value>wx_gui</value>
+    </param>
+    <param>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>run_options</key>
+      <value>prompt</value>
+    </param>
+    <param>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>realtime_scheduling</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(10, 10)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>10**(-snr_db/10)</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(389, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>prefix</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>"/n/harrisville/x/anastas/gnuradio_trunk/"</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(590, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(764, 16)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable_slider</key>
+    <param>
+      <key>id</key>
+      <value>snr_db</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>label</key>
+      <value>SNR (dB)</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>-10</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>num_steps</key>
+      <value>100</value>
+    </param>
+    <param>
+      <key>style</key>
+      <value>wx.SL_HORIZONTAL</value>
+    </param>
+    <param>
+      <key>converver</key>
+      <value>float_converter</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(229, 13)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_multiply_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_multiply_xx_2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(392, 591)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_short_to_float</key>
+    <param>
+      <key>id</key>
+      <value>gr_short_to_float_1_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(535, 609)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_numbersink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_numbersink2_3_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>units</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>min_value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max_value</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>factor</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>decimal_places</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>number_rate</key>
+      <value>15</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0.001</value>
+    </param>
+    <param>
+      <key>show_gauge</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1,0,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(713, 426)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_noise_source_x</key>
+    <param>
+      <key>id</key>
+      <value>gr_noise_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>noise_type</key>
+      <value>gr.GR_GAUSSIAN</value>
+    </param>
+    <param>
+      <key>amp</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>seed</key>
+      <value>42</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(672, 290)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_add_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_add_xx_1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(951, 256)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_scopesink2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Scope Plot</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>v_offset</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>trig_mode</key>
+      <value>gr.gr_TRIG_MODE_AUTO</value>
+    </param>
+    <param>
+      <key>y_axis_label</key>
+      <value>Counts</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(952, 73)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>random_source_x</key>
+    <param>
+      <key>id</key>
+      <value>random_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_samps</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(21, 170)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_throttle</key>
+    <param>
+      <key>id</key>
+      <value>gr_throttle_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>samples_per_second</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(517, 103)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_sub_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_sub_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(217, 597)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_chunks_to_symbols_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_chunks_to_symbols_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>in_type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>symbol_table</key>
+      <value>-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7,0,   0,-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7</value>
+    </param>
+    <param>
+      <key>dimension</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(551, 184)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_pccc_encoder_xx</key>
+    <param>
+      <key>id</key>
+      <value>trellis_pccc_encoder_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>ss</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>interleaver_args</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>bl</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(236, 147)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_pccc_decoder_x</key>
+    <param>
+      <key>id</key>
+      <value>trellis_pccc_decoder_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>s</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>o_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>interleaver</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>block_size</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>iterations</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>siso_type</key>
+      <value>trellis.TRELLIS_MIN_SUM</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(357, 304)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_metrics_x</key>
+    <param>
+      <key>id</key>
+      <value>trellis_metrics_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>f</value>
+    </param>
+    <param>
+      <key>card</key>
+      <value>16</value>
+    </param>
+    <param>
+      <key>dim</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>table</key>
+      <value>-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7,0,   0,-7,0, -5,0, -3,0, -1,0, 1,0, 3,0, 5,0, 7</value>
+    </param>
+    <param>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(58, 354)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>100e3</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(482, 17)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_throttle_0</source_block_id>
+    <sink_block_id>gr_chunks_to_symbols_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>wxgui_scopesink2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_noise_source_x_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_chunks_to_symbols_xx_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_multiply_xx_2_0</source_block_id>
+    <sink_block_id>gr_short_to_float_1_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_short_to_float_1_0</source_block_id>
+    <sink_block_id>wxgui_numbersink2_3_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>trellis_metrics_x_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>trellis_pccc_encoder_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_pccc_encoder_xx_0</source_block_id>
+    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_metrics_x_0</source_block_id>
+    <sink_block_id>trellis_pccc_decoder_x_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_pccc_decoder_x_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+</flow_graph>
diff --git a/gnuradio-examples/grc/trellis/readme.txt b/gnuradio-examples/grc/trellis/readme.txt
index d620fd628..9c7363af8 100644
--- a/gnuradio-examples/grc/trellis/readme.txt
+++ b/gnuradio-examples/grc/trellis/readme.txt
@@ -1,5 +1,7 @@
-This is an example of using gr-trellis in grc.
+These are examples of using gr-trellis in grc.
 
+INTERFERENCE CANCELLATION
+-------------------------
 Two users are transmitting simultaneously using convolutionally encoded QPSK, each with power P1=alpha*P and P2=(1-alpha)*P.
 The combined signal is observed in noise and four different receivers are considered:
 1) A viterbi decoder decoding user 1 assuming user 2 is noise
@@ -13,4 +15,18 @@ The combined signal is observed in noise and four different receivers are consid
 
 You can change the signal to noise ratio P/sigma^2 and the allocation of power to the two users, alpha.
 
+
+Serially Concatenated Convolutional Codes
+-----------------------------------------
+An SCCC can be defined by an outer and an inner FSM together with an interleaver
+and a modulation type. You can change the SNR and observe the estimated BER.
+In sccc.grc the decoding and metric calculation are combined; in sccc1.grc they are separate.
+
+Parallel Concatenated Convolutional Codes
+-----------------------------------------
+A PCCC can be defined by two FSMs together with an interleaver
+and a modulation type. You can change the SNR and observe the estimated BER.
+In pccc1.grc the decoding and metric calculation are separate.
+
+
 Enjoy.
diff --git a/gnuradio-examples/grc/trellis/sccc.grc b/gnuradio-examples/grc/trellis/sccc.grc
new file mode 100644
index 000000000..e8f656f63
--- /dev/null
+++ b/gnuradio-examples/grc/trellis/sccc.grc
@@ -0,0 +1,832 @@
+<?xml version='1.0' encoding='ASCII'?>
+<flow_graph>
+  <timestamp>Wed Aug 31 19:57:09 2011</timestamp>
+  <block>
+    <key>options</key>
+    <param>
+      <key>id</key>
+      <value>sccc</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Serially Concatenated Convolutional Code</value>
+    </param>
+    <param>
+      <key>author</key>
+      <value>AA</value>
+    </param>
+    <param>
+      <key>description</key>
+      <value>gnuradio flow graph</value>
+    </param>
+    <param>
+      <key>window_size</key>
+      <value>2048, 2048</value>
+    </param>
+    <param>
+      <key>generate_options</key>
+      <value>wx_gui</value>
+    </param>
+    <param>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>run_options</key>
+      <value>prompt</value>
+    </param>
+    <param>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>realtime_scheduling</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(10, 10)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>10**(-snr_db/10)</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(389, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>random_source_x</key>
+    <param>
+      <key>id</key>
+      <value>random_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_samps</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(21, 170)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>prefix</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>"/n/harrisville/x/anastas/gnuradio_trunk/"</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(590, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(764, 16)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_add_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_add_xx_1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>complex</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(951, 256)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_sub_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_sub_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(445, 517)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_multiply_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_multiply_xx_2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(228.25, 798.39170361874085)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_short_to_float</key>
+    <param>
+      <key>id</key>
+      <value>gr_short_to_float_1_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(416, 815)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable_slider</key>
+    <param>
+      <key>id</key>
+      <value>snr_db</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>label</key>
+      <value>SNR (dB)</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>-10</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>num_steps</key>
+      <value>100</value>
+    </param>
+    <param>
+      <key>style</key>
+      <value>wx.SL_HORIZONTAL</value>
+    </param>
+    <param>
+      <key>converver</key>
+      <value>float_converter</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(229, 13)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>10e3</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(482, 17)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_scopesink2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>complex</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Scope Plot</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>v_offset</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>trig_mode</key>
+      <value>gr.gr_TRIG_MODE_AUTO</value>
+    </param>
+    <param>
+      <key>y_axis_label</key>
+      <value>Counts</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(952, 73)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_throttle</key>
+    <param>
+      <key>id</key>
+      <value>gr_throttle_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>samples_per_second</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(514, 105)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_chunks_to_symbols_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_chunks_to_symbols_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>in_type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>complex</value>
+    </param>
+    <param>
+      <key>symbol_table</key>
+      <value>1,0,1j,0,-1j,0,-1,0,   0,1,0,1j,0,-1j,0,-1</value>
+    </param>
+    <param>
+      <key>dimension</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(551, 184)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_noise_source_x</key>
+    <param>
+      <key>id</key>
+      <value>gr_noise_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>complex</value>
+    </param>
+    <param>
+      <key>noise_type</key>
+      <value>gr.GR_GAUSSIAN</value>
+    </param>
+    <param>
+      <key>amp</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>seed</key>
+      <value>42</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(672, 290)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_sccc_encoder_xx</key>
+    <param>
+      <key>id</key>
+      <value>trellis_sccc_encoder_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>ss</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn2o3_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>interleaver_args</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>bl</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(242, 154)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_numbersink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_numbersink2_3_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>units</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>min_value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max_value</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>factor</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>decimal_places</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>number_rate</key>
+      <value>15</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0.001</value>
+    </param>
+    <param>
+      <key>show_gauge</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1,0,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(688, 572)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_sccc_decoder_combined_xx</key>
+    <param>
+      <key>id</key>
+      <value>trellis_sccc_decoder_combined_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>c</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>s</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>o_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn2o3_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>interleaver</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>block_size</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>iterations</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>dim</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>table</key>
+      <value>1,0,1j,0,-1j,0,-1,0,   0,1,0,1j,0,-1j,0,-1</value>
+    </param>
+    <param>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
+    </param>
+    <param>
+      <key>siso_type</key>
+      <value>trellis.TRELLIS_SUM_PRODUCT</value>
+    </param>
+    <param>
+      <key>scaling</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(159, 335)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_throttle_0</source_block_id>
+    <sink_block_id>gr_chunks_to_symbols_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>wxgui_scopesink2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_noise_source_x_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_chunks_to_symbols_xx_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>trellis_sccc_encoder_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_sccc_encoder_xx_0</source_block_id>
+    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>trellis_sccc_decoder_combined_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_sccc_decoder_combined_xx_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_multiply_xx_2_0</source_block_id>
+    <sink_block_id>gr_short_to_float_1_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_short_to_float_1_0</source_block_id>
+    <sink_block_id>wxgui_numbersink2_3_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+</flow_graph>
diff --git a/gnuradio-examples/grc/trellis/sccc1.grc b/gnuradio-examples/grc/trellis/sccc1.grc
new file mode 100644
index 000000000..0be59d0c4
--- /dev/null
+++ b/gnuradio-examples/grc/trellis/sccc1.grc
@@ -0,0 +1,857 @@
+<?xml version='1.0' encoding='ASCII'?>
+<flow_graph>
+  <timestamp>Wed Aug 31 20:09:23 2011</timestamp>
+  <block>
+    <key>options</key>
+    <param>
+      <key>id</key>
+      <value>sccc1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Serially Concatenated Convolutional Code</value>
+    </param>
+    <param>
+      <key>author</key>
+      <value>AA</value>
+    </param>
+    <param>
+      <key>description</key>
+      <value>gnuradio flow graph</value>
+    </param>
+    <param>
+      <key>window_size</key>
+      <value>2048, 2048</value>
+    </param>
+    <param>
+      <key>generate_options</key>
+      <value>wx_gui</value>
+    </param>
+    <param>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>run_options</key>
+      <value>prompt</value>
+    </param>
+    <param>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>realtime_scheduling</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(10, 10)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>10**(-snr_db/10)</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(389, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>random_source_x</key>
+    <param>
+      <key>id</key>
+      <value>random_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>num_samps</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(21, 170)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>prefix</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>"/n/harrisville/x/anastas/gnuradio_trunk/"</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(590, 15)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1000</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(764, 16)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable_slider</key>
+    <param>
+      <key>id</key>
+      <value>snr_db</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>label</key>
+      <value>SNR (dB)</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>min</key>
+      <value>-10</value>
+    </param>
+    <param>
+      <key>max</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>num_steps</key>
+      <value>100</value>
+    </param>
+    <param>
+      <key>style</key>
+      <value>wx.SL_HORIZONTAL</value>
+    </param>
+    <param>
+      <key>converver</key>
+      <value>float_converter</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(229, 13)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>10e3</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(482, 17)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_sccc_encoder_xx</key>
+    <param>
+      <key>id</key>
+      <value>trellis_sccc_encoder_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>ss</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn2o3_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>interleaver_args</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>bl</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(242, 154)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_sccc_decoder_x</key>
+    <param>
+      <key>id</key>
+      <value>trellis_sccc_decoder_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>s</value>
+    </param>
+    <param>
+      <key>o_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn1o2_4.fsm"</value>
+    </param>
+    <param>
+      <key>o_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>o_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>i_fsm_args</key>
+      <value>prefix+"gr-trellis/src/examples/fsm_files/awgn2o3_4.fsm"</value>
+    </param>
+    <param>
+      <key>i_init_state</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>i_final_state</key>
+      <value>-1</value>
+    </param>
+    <param>
+      <key>interleaver</key>
+      <value>trellis.interleaver(block,666)</value>
+    </param>
+    <param>
+      <key>block_size</key>
+      <value>block</value>
+    </param>
+    <param>
+      <key>iterations</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>siso_type</key>
+      <value>trellis.TRELLIS_MIN_SUM</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(333, 305)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_sub_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_sub_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(217, 597)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_multiply_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_multiply_xx_2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(392, 591)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_short_to_float</key>
+    <param>
+      <key>id</key>
+      <value>gr_short_to_float_1_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(535, 609)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_numbersink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_numbersink2_3_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>units</key>
+      <value>BER</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>min_value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>max_value</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>factor</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>decimal_places</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>number_rate</key>
+      <value>15</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0.001</value>
+    </param>
+    <param>
+      <key>show_gauge</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1,0,1,1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(713, 426)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_noise_source_x</key>
+    <param>
+      <key>id</key>
+      <value>gr_noise_source_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>noise_type</key>
+      <value>gr.GR_GAUSSIAN</value>
+    </param>
+    <param>
+      <key>amp</key>
+      <value>noisevar</value>
+    </param>
+    <param>
+      <key>seed</key>
+      <value>42</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(672, 290)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_add_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_add_xx_1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(951, 256)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>trellis_metrics_x</key>
+    <param>
+      <key>id</key>
+      <value>trellis_metrics_x_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>f</value>
+    </param>
+    <param>
+      <key>card</key>
+      <value>8</value>
+    </param>
+    <param>
+      <key>dim</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>table</key>
+      <value>-7, -5, -3, -1, 1, 3, 5, 7</value>
+    </param>
+    <param>
+      <key>metric_type</key>
+      <value>trellis.TRELLIS_EUCLIDEAN</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(58, 354)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_throttle</key>
+    <param>
+      <key>id</key>
+      <value>gr_throttle_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>samples_per_second</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(517, 103)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>wxgui_scopesink2_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Scope Plot</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>R</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>v_offset</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>trig_mode</key>
+      <value>gr.gr_TRIG_MODE_AUTO</value>
+    </param>
+    <param>
+      <key>y_axis_label</key>
+      <value>Counts</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(952, 73)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_chunks_to_symbols_xx</key>
+    <param>
+      <key>id</key>
+      <value>gr_chunks_to_symbols_xx_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>in_type</key>
+      <value>short</value>
+    </param>
+    <param>
+      <key>out_type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>symbol_table</key>
+      <value>-7, -5, -3, -1, 1, 3, 5, 7</value>
+    </param>
+    <param>
+      <key>dimension</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(551, 184)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_throttle_0</source_block_id>
+    <sink_block_id>gr_chunks_to_symbols_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>wxgui_scopesink2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_noise_source_x_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_chunks_to_symbols_xx_0</source_block_id>
+    <sink_block_id>gr_add_xx_1</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>random_source_x_0</source_block_id>
+    <sink_block_id>trellis_sccc_encoder_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_sccc_encoder_xx_0</source_block_id>
+    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_multiply_xx_2_0</source_block_id>
+    <sink_block_id>gr_short_to_float_1_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_short_to_float_1_0</source_block_id>
+    <sink_block_id>wxgui_numbersink2_3_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_sub_xx_0</source_block_id>
+    <sink_block_id>gr_multiply_xx_2_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gr_add_xx_1</source_block_id>
+    <sink_block_id>trellis_metrics_x_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_metrics_x_0</source_block_id>
+    <sink_block_id>trellis_sccc_decoder_x_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>trellis_sccc_decoder_x_0</source_block_id>
+    <sink_block_id>gr_sub_xx_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>1</sink_key>
+  </connection>
+</flow_graph>
diff --git a/gnuradio-examples/python/Makefile.am b/gnuradio-examples/python/Makefile.am
index eba4c14ab..3f1977e74 100644
--- a/gnuradio-examples/python/Makefile.am
+++ b/gnuradio-examples/python/Makefile.am
@@ -31,5 +31,6 @@ SUBDIRS = \
 	network \
 	ofdm \
 	pfb \
+	tags \
 	usrp \
 	usrp2
diff --git a/gnuradio-examples/python/ofdm/gr_plot_ofdm.py b/gnuradio-examples/python/ofdm/gr_plot_ofdm.py
index e3b347189..b24855148 100755
--- a/gnuradio-examples/python/ofdm/gr_plot_ofdm.py
+++ b/gnuradio-examples/python/ofdm/gr_plot_ofdm.py
@@ -20,14 +20,24 @@
 # Boston, MA 02110-1301, USA.
 # 
 
-import scipy, pylab, math
-import struct, sys
-from pylab import *
-from matplotlib.font_manager import fontManager, FontProperties
+import math, struct, sys
 from optparse import OptionParser
-from scipy import fftpack
 from math import log10
 
+try:
+    import scipy
+    from scipy import fftpack
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    from pylab import *
+    from matplotlib.font_manager import fontManager, FontProperties
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
+
 matplotlib.interactive(True)
 matplotlib.use('TkAgg')
 
diff --git a/gnuradio-examples/python/pfb/channelize.py b/gnuradio-examples/python/pfb/channelize.py
index f845c05c6..999e5d20e 100755
--- a/gnuradio-examples/python/pfb/channelize.py
+++ b/gnuradio-examples/python/pfb/channelize.py
@@ -21,10 +21,21 @@
 # 
 
 from gnuradio import gr, blks2
-import os, time
-import scipy, pylab
-from scipy import fftpack
-from pylab import mlab
+import sys, time
+
+try:
+    import scipy
+    from scipy import fftpack
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+    from pylab import mlab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 class pfb_top_block(gr.top_block):
     def __init__(self):
diff --git a/gnuradio-examples/python/pfb/chirp_channelize.py b/gnuradio-examples/python/pfb/chirp_channelize.py
index edebf5f59..951255d3b 100755
--- a/gnuradio-examples/python/pfb/chirp_channelize.py
+++ b/gnuradio-examples/python/pfb/chirp_channelize.py
@@ -21,10 +21,21 @@
 # 
 
 from gnuradio import gr, blks2
-import os, time
-import scipy, pylab
-from scipy import fftpack
-from pylab import mlab
+import sys, time
+
+try:
+    import scipy
+    from scipy import fftpack
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+    from pylab import mlab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 class pfb_top_block(gr.top_block):
     def __init__(self):
diff --git a/gnuradio-examples/python/pfb/decimate.py b/gnuradio-examples/python/pfb/decimate.py
index cb5d61b72..643a2c241 100755
--- a/gnuradio-examples/python/pfb/decimate.py
+++ b/gnuradio-examples/python/pfb/decimate.py
@@ -21,14 +21,21 @@
 # 
 
 from gnuradio import gr, blks2
-import os
-import scipy, pylab
-from scipy import fftpack
-from pylab import mlab
-import time
-
-#print os.getpid()
-#raw_input()
+import sys, time
+
+try:
+    import scipy
+    from scipy import fftpack
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+    from pylab import mlab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 class pfb_top_block(gr.top_block):
     def __init__(self):
diff --git a/gnuradio-examples/python/pfb/fmtest.py b/gnuradio-examples/python/pfb/fmtest.py
index 97df0e0f5..635ee4e9e 100755
--- a/gnuradio-examples/python/pfb/fmtest.py
+++ b/gnuradio-examples/python/pfb/fmtest.py
@@ -1,14 +1,42 @@
 #!/usr/bin/env python
 #
+# Copyright 2009 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+from gnuradio import gr, blks2
+import sys, math, time
+
+try:
+    import scipy
+    from scipy import fftpack
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 
-from gnuradio import gr, eng_notation
-from gnuradio import blks2
-from gnuradio.eng_option import eng_option
-from optparse import OptionParser
-import math, time, sys, scipy, pylab
-from scipy import fftpack
-
 class fmtx(gr.hier_block2):
     def __init__(self, lo_freq, audio_rate, if_rate):
 
diff --git a/gnuradio-examples/python/pfb/interpolate.py b/gnuradio-examples/python/pfb/interpolate.py
index a7a2522f8..370cf26a7 100755
--- a/gnuradio-examples/python/pfb/interpolate.py
+++ b/gnuradio-examples/python/pfb/interpolate.py
@@ -21,14 +21,21 @@
 # 
 
 from gnuradio import gr, blks2
-import os
-import scipy, pylab
-from scipy import fftpack
-from pylab import mlab
-import time
-
-#print os.getpid()
-#raw_input()
+import sys, time
+
+try:
+    import scipy
+    from scipy import fftpack
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+    from pylab import mlab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 class pfb_top_block(gr.top_block):
     def __init__(self):
diff --git a/gnuradio-examples/python/pfb/resampler.py b/gnuradio-examples/python/pfb/resampler.py
index 6be7cf14e..7b296ca71 100755
--- a/gnuradio-examples/python/pfb/resampler.py
+++ b/gnuradio-examples/python/pfb/resampler.py
@@ -1,7 +1,39 @@
 #!/usr/bin/env python
+#
+# Copyright 2009 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
 
 from gnuradio import gr, blks2
-import scipy, pylab
+import sys
+
+try:
+    import scipy
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 class mytb(gr.top_block):
     def __init__(self, fs_in, fs_out, fc, N=10000):
diff --git a/gnuradio-examples/python/pfb/synth_filter.py b/gnuradio-examples/python/pfb/synth_filter.py
index a1562f9ea..074d9cb2c 100755
--- a/gnuradio-examples/python/pfb/synth_filter.py
+++ b/gnuradio-examples/python/pfb/synth_filter.py
@@ -21,7 +21,19 @@
 # 
 
 from gnuradio import gr, blks2
-import scipy, pylab
+import sys 
+
+try:
+    import scipy
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 def main():
     N = 1000000
diff --git a/gnuradio-examples/python/pfb/synth_to_chan.py b/gnuradio-examples/python/pfb/synth_to_chan.py
index 1beda1a54..7e454d903 100755
--- a/gnuradio-examples/python/pfb/synth_to_chan.py
+++ b/gnuradio-examples/python/pfb/synth_to_chan.py
@@ -21,7 +21,19 @@
 # 
 
 from gnuradio import gr, blks2
-import scipy, pylab
+import sys 
+
+try:
+    import scipy
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
+
+try:
+    import pylab
+except ImportError:
+    print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)."
+    sys.exit(1)
 
 def main():
     N = 1000000
diff --git a/gnuradio-examples/python/tags/.gitignore b/gnuradio-examples/python/tags/.gitignore
new file mode 100644
index 000000000..b336cc7ce
--- /dev/null
+++ b/gnuradio-examples/python/tags/.gitignore
@@ -0,0 +1,2 @@
+/Makefile
+/Makefile.in
diff --git a/gnuradio-examples/python/tags/Makefile.am b/gnuradio-examples/python/tags/Makefile.am
new file mode 100644
index 000000000..5d71bf9b0
--- /dev/null
+++ b/gnuradio-examples/python/tags/Makefile.am
@@ -0,0 +1,29 @@
+#
+# Copyright 2011 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+include $(top_srcdir)/Makefile.common
+
+ourdatadir = $(exampledir)/tags
+
+dist_ourdata_SCRIPTS =		\
+	test_file_tags.py	\
+	uhd_burst_detector.py
+
diff --git a/gnuradio-examples/python/tags/test_file_tags.py b/gnuradio-examples/python/tags/test_file_tags.py
index 4ff4549ef..446986cd7 100755
--- a/gnuradio-examples/python/tags/test_file_tags.py
+++ b/gnuradio-examples/python/tags/test_file_tags.py
@@ -1,7 +1,33 @@
 #!/usr/bin/env python
+#
+# Copyright 2011 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
 
 from gnuradio import gr
-import scipy
+import sys
+
+try:
+    import scipy
+except ImportError:
+    print "Error: Program requires scipy (see: www.scipy.org)."
+    sys.exit(1)
 
 def main():
     data = scipy.arange(0, 32000, 1).tolist()
diff --git a/gnuradio-examples/python/tags/uhd_burst_detector.py b/gnuradio-examples/python/tags/uhd_burst_detector.py
index f8ebbe66a..ffa419562 100755
--- a/gnuradio-examples/python/tags/uhd_burst_detector.py
+++ b/gnuradio-examples/python/tags/uhd_burst_detector.py
@@ -1,4 +1,24 @@
 #!/usr/bin/env python
+#
+# Copyright 2011 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
 
 from gnuradio import eng_notation
 from gnuradio import gr
@@ -9,16 +29,16 @@ from gnuradio.gr import firdes
 from optparse import OptionParser
 
 class uhd_burst_detector(gr.top_block):
-    def __init__(self, frequency, sample_rate,
-                 uhd_address="192.168.10.2", trigger=False):
+    def __init__(self, uhd_address, options):
 
         gr.top_block.__init__(self)
 
-        self.freq = frequency
-        self.samp_rate = sample_rate
         self.uhd_addr = uhd_address
-        self.gain = 32
-        self.trigger = trigger
+        self.freq = options.freq
+        self.samp_rate = options.samp_rate
+        self.gain = options.gain
+        self.threshold = options.threshold
+        self.trigger = options.trigger
         
         self.uhd_src = uhd.single_usrp_source(
             device_addr=self.uhd_addr,
@@ -32,7 +52,6 @@ class uhd_burst_detector(gr.top_block):
 
         taps = firdes.low_pass_2(1, 1, 0.4, 0.1, 60)
         self.chanfilt = gr.fir_filter_ccc(10, taps)
-        self.ann0 = gr.annotator_alltoall(100000, gr.sizeof_gr_complex)
         self.tagger = gr.burst_tagger(gr.sizeof_gr_complex)
 
         # Dummy signaler to collect a burst on known periods
@@ -40,11 +59,18 @@ class uhd_burst_detector(gr.top_block):
         self.signal = gr.vector_source_s(data, True)
 
         # Energy detector to get signal burst
+        ## use squelch to detect energy
+        self.det  = gr.simple_squelch_cc(self.threshold, 0.01)
+        ## convert to mag squared (float)
         self.c2m = gr.complex_to_mag_squared()
-        self.iir = gr.single_pole_iir_filter_ff(0.0001)
-        self.sub = gr.sub_ff()
-        self.mult = gr.multiply_const_ff(32768)
+        ## average to debounce
+        self.avg = gr.single_pole_iir_filter_ff(0.01)
+        ## rescale signal for conversion to short
+        self.scale = gr.multiply_const_ff(2**16)
+        ## signal input uses shorts
         self.f2s = gr.float_to_short()
+
+        # Use file sink burst tagger to capture bursts
         self.fsnk = gr.tagged_file_sink(gr.sizeof_gr_complex, self.samp_rate)
         
 
@@ -60,17 +86,12 @@ class uhd_burst_detector(gr.top_block):
 
         else:
             # Connect an energy detector signaler to the burst tagger
-            self.connect((self.uhd_src, 0), (self.c2m, 0))
-            self.connect((self.c2m, 0), (self.sub, 0))
-            self.connect((self.c2m, 0), (self.iir, 0))
-            self.connect((self.iir, 0), (self.sub, 1))
-            self.connect((self.sub, 0), (self.mult,0))
-            self.connect((self.mult, 0), (self.f2s, 0))
-            self.connect((self.f2s, 0), (self.tagger, 1))
+            self.connect(self.uhd_src, self.det)
+            self.connect(self.det, self.c2m, self.avg, self.scale, self.f2s)
+            self.connect(self.f2s, (self.tagger, 1))
         
     def set_samp_rate(self, samp_rate):
         self.samp_rate = samp_rate
-        self.wxgui_fftsink2_0.set_sample_rate(self.samp_rate/10)
         self.uhd_src_0.set_samp_rate(self.samp_rate)
             
 if __name__ == '__main__':
@@ -83,16 +104,15 @@ if __name__ == '__main__':
                       help="set frequency to FREQ", metavar="FREQ")
     parser.add_option("-g", "--gain", type="eng_float", default=0,
                       help="set gain in dB [default=%default]")
-    parser.add_option("-R", "--rate", type="eng_float", default=200000,
+    parser.add_option("-R", "--samp-rate", type="eng_float", default=200000,
                       help="set USRP sample rate [default=%default]")
+    parser.add_option("-t", "--threshold", type="float", default=-60,
+                      help="Set the detection power threshold (dBm) [default=%default")
     parser.add_option("-T", "--trigger", action="store_true", default=False,
                       help="Use internal trigger instead of detector [default=%default]")
     (options, args) = parser.parse_args()
     
-    frequency = options.freq
-    samp_rate = samp_rate = options.rate
     uhd_addr = options.address
-    trigger = options.trigger
 
-    tb = uhd_burst_detector(frequency, samp_rate, uhd_addr, trigger)
+    tb = uhd_burst_detector(uhd_addr, options)
     tb.run()