diff --git a/lib/demapping/universal_ctrl_chans_demapper_impl.cc b/lib/demapping/universal_ctrl_chans_demapper_impl.cc
index c563f7d..a5617c0 100644
--- a/lib/demapping/universal_ctrl_chans_demapper_impl.cc
+++ b/lib/demapping/universal_ctrl_chans_demapper_impl.cc
@@ -33,22 +33,24 @@
   namespace gsm {
 
     universal_ctrl_chans_demapper::sptr
-    universal_ctrl_chans_demapper::make(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
+    universal_ctrl_chans_demapper::make(unsigned int timeslot_nr, const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
     {
       return gnuradio::get_initial_sptr
-        (new universal_ctrl_chans_demapper_impl(starts_fn_mod51, channel_types));
+        (new universal_ctrl_chans_demapper_impl(timeslot_nr, starts_fn_mod51, channel_types));
     }
 
     /*
      * The private constructor
      */
-    universal_ctrl_chans_demapper_impl::universal_ctrl_chans_demapper_impl(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
+    universal_ctrl_chans_demapper_impl::universal_ctrl_chans_demapper_impl(unsigned int timeslot_nr, const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
       : gr::block("universal_ctrl_chans_demapper",
               gr::io_signature::make(0, 0, 0),
-              gr::io_signature::make(0, 0, 0))
+              gr::io_signature::make(0, 0, 0)),
+       d_timeslot(timeslot_nr)
+              
     {
     
-        d_timeslot=0;
+        
         for(int ii=0; ii<51; ii++)
         {
             d_starts_fn_mod51[ii]=0;
diff --git a/lib/demapping/universal_ctrl_chans_demapper_impl.h b/lib/demapping/universal_ctrl_chans_demapper_impl.h
index 60cdc5d..aade90d 100644
--- a/lib/demapping/universal_ctrl_chans_demapper_impl.h
+++ b/lib/demapping/universal_ctrl_chans_demapper_impl.h
@@ -37,7 +37,7 @@
       uint32_t d_frame_numbers[4];
       pmt::pmt_t d_bursts[4];
      public:
-      universal_ctrl_chans_demapper_impl(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types);
+      universal_ctrl_chans_demapper_impl(unsigned int timeslot_nr, const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types);
       ~universal_ctrl_chans_demapper_impl();
 
       void filter_ctrl_chans(pmt::pmt_t msg);