diff --git a/lib/transmitter/txtime_setter_impl.cc b/lib/transmitter/txtime_setter_impl.cc
index 91fc4ca..f6141f0 100644
--- a/lib/transmitter/txtime_setter_impl.cc
+++ b/lib/transmitter/txtime_setter_impl.cc
@@ -1,6 +1,7 @@
 /* -*- c++ -*- */
 /* @file
  * @author Piotr Krysik <ptrkrysik@gmail.com>
+ * @author Vadim Yanitskiy <axilirator@gmail.com>
  * @section LICENSE
  * 
  * Gr-gsm is free software; you can redistribute it and/or modify
@@ -26,38 +27,55 @@
 
 #include <gnuradio/io_signature.h>
 #include <grgsm/gsmtap.h>
+
 #include "txtime_setter_impl.h"
 
 namespace gr {
   namespace gsm {
 
     txtime_setter::sptr
-    txtime_setter::make(uint32_t init_fn, uint64_t init_time_secs, double init_time_fracs, uint64_t time_hint_secs, double time_hint_fracs, double timing_advance, double delay_correction)
+    txtime_setter::make(
+      uint32_t init_fn, uint64_t init_time_secs,
+      double init_time_fracs, uint64_t time_hint_secs,
+      double time_hint_fracs, double timing_advance,
+      double delay_correction)
     {
       return gnuradio::get_initial_sptr
-        (new txtime_setter_impl(init_fn, init_time_secs, init_time_fracs, time_hint_secs, time_hint_fracs, timing_advance, delay_correction));
+        (new txtime_setter_impl(init_fn, init_time_secs,
+          init_time_fracs, time_hint_secs, time_hint_fracs,
+          timing_advance, delay_correction));
     }
 
     /*
      * The private constructor
      */
-    txtime_setter_impl::txtime_setter_impl(uint32_t init_fn, uint64_t init_time_secs, double init_time_fracs, uint64_t time_hint_secs, double time_hint_fracs, double timing_advance, double delay_correction)
-      : gr::block("txtime_setter",
-              gr::io_signature::make(0, 0, 0),
-              gr::io_signature::make(0, 0, 0)),
-        d_fn_ref(init_fn),
-        d_ts_ref(0),
-        d_time_ref(init_time_secs,init_time_fracs),
+    txtime_setter_impl::txtime_setter_impl(
+      uint32_t init_fn, uint64_t init_time_secs,
+      double init_time_fracs, uint64_t time_hint_secs,
+      double time_hint_fracs, double timing_advance,
+      double delay_correction
+    ) : gr::block("txtime_setter",
+          gr::io_signature::make(0, 0, 0),
+          gr::io_signature::make(0, 0, 0)),
         d_time_hint(time_hint_secs,time_hint_fracs),
+        d_time_ref(init_time_secs,init_time_fracs),
+        d_delay_correction(delay_correction),
         d_timing_advance(timing_advance),
-        d_delay_correction(delay_correction)
+        d_fn_ref(init_fn),
+        d_ts_ref(0)
     {
-        message_port_register_in(pmt::intern("fn_time"));
-        message_port_register_in(pmt::intern("bursts_in"));
-        message_port_register_out(pmt::intern("bursts_out"));
+        // Register I/O ports
+        message_port_register_in(pmt::mp("fn_time"));
+        message_port_register_in(pmt::mp("bursts_in"));
+        message_port_register_out(pmt::mp("bursts_out"));
 
-        set_msg_handler(pmt::intern("fn_time"), boost::bind(&txtime_setter_impl::process_fn_time_reference, this, _1));
-        set_msg_handler(pmt::intern("bursts_in"),  boost::bind(&txtime_setter_impl::process_txtime_of_burst,   this, _1));
+        // Bind message handlers
+        set_msg_handler(pmt::mp("fn_time"),
+          boost::bind(&txtime_setter_impl::process_fn_time_reference,
+            this, _1));
+        set_msg_handler(pmt::mp("bursts_in"),
+          boost::bind(&txtime_setter_impl::process_txtime_of_burst,
+            this, _1));
     }
 
     /*
@@ -69,60 +87,84 @@
     
     void txtime_setter_impl::process_fn_time_reference(pmt::pmt_t msg)
     {
-//      d_time_hint = pmt::to_python(pmt::dict_ref(msg, pmt::intern("time_hint"), pmt::PMT_NIL))
-        pmt::pmt_t not_found = pmt::intern("not_found");
-        pmt::pmt_t fn_time = pmt::dict_ref(msg, pmt::intern("fn_time"), not_found);
-        pmt::pmt_t time_hint = pmt::dict_ref(msg, pmt::intern("fn_time"), not_found);
+      pmt::pmt_t not_found = pmt::intern("not_found");
+      pmt::pmt_t fn_time, time_hint;
 
-        if(fn_time != not_found)
-        {
-          uint32_t fn_ref = static_cast<uint32_t>(pmt::to_uint64(pmt::car(pmt::car(fn_time))));
-          uint32_t ts =  static_cast<uint32_t>(pmt::to_uint64(pmt::cdr(pmt::car(fn_time))));
-          uint64_t time_secs = pmt::to_uint64(pmt::car(pmt::cdr(fn_time)));
-          double time_fracs = pmt::to_double(pmt::cdr(pmt::cdr(fn_time)));
-          set_fn_time_reference(fn_ref, ts,  time_secs, time_fracs);
-        } else if(time_hint != not_found) {
-          set_time_hint(pmt::to_uint64(pmt::car(fn_time)), pmt::to_double(pmt::cdr(fn_time)));
-        }
+      fn_time = pmt::dict_ref(msg,
+        pmt::intern("fn_time"), not_found);
+      time_hint = pmt::dict_ref(msg,
+        pmt::intern("fn_time"), not_found);
 
+      if (fn_time != not_found) {
+        uint32_t fn_ref = static_cast<uint32_t>
+          (pmt::to_uint64(pmt::car(pmt::car(fn_time))));
+        uint32_t ts = static_cast<uint32_t>
+          (pmt::to_uint64(pmt::cdr(pmt::car(fn_time))));
+        uint64_t time_secs = pmt::to_uint64(
+          pmt::car(pmt::cdr(fn_time)));
+        double time_fracs = pmt::to_double(
+          pmt::cdr(pmt::cdr(fn_time)));
+
+        set_fn_time_reference(fn_ref, ts, time_secs, time_fracs);
+      } else if (time_hint != not_found) {
+        set_time_hint(pmt::to_uint64(pmt::car(fn_time)),
+          pmt::to_double(pmt::cdr(fn_time)));
+      }
     }
-    
-    void txtime_setter_impl::process_txtime_of_burst(pmt::pmt_t burst)
+
+    void txtime_setter_impl::process_txtime_of_burst(pmt::pmt_t msg_in)
     {
-        pmt::pmt_t header_plus_burst = pmt::cdr(burst);
-        int8_t * burst_int8 = (int8_t *)pmt::blob_data(header_plus_burst);        
-        gsmtap_hdr * header = (gsmtap_hdr *)(burst_int8);
-        
-        uint32_t frame_nr = be32toh(header->frame_number); 
-        uint32_t ts_num = header->timeslot;
-        
-        if(d_fn_ref != 0xffffffff)
-        {
-          time_format txtime = fn_time_delta_cpp(d_fn_ref, d_time_ref, frame_nr, d_time_hint, ts_num, d_ts_ref);
-          time_spec_t txtime_spec = time_spec_t(txtime.first, txtime.second);
-          txtime_spec = txtime_spec - d_delay_correction;
-          txtime_spec = txtime_spec - d_timing_advance;
-          
-          if(txtime_spec <= time_spec_t(d_time_hint.first, d_time_hint.second))
-          {
-            std::cout << "lB" << std::flush;
-          }
-          else if(txtime_spec > time_spec_t(d_time_hint.first, d_time_hint.second)+10.0)
-          {
-            std::cout << "eB" << std::flush;
-          }
-          else
-          {
-            pmt::pmt_t tags_dict = pmt::dict_add(pmt::make_dict(), pmt::intern("tx_time"), pmt::make_tuple(pmt::from_uint64(txtime_spec.get_full_secs()),pmt::from_double(txtime_spec.get_frac_secs())));
-            tags_dict = pmt::dict_add(tags_dict, pmt::intern("fn"), pmt::from_uint64(frame_nr));
-            tags_dict = pmt::dict_add(tags_dict, pmt::intern("ts"), pmt::from_uint64(ts_num));
-            pmt::pmt_t new_msg = pmt::cons(tags_dict, pmt::cdr(burst));
-            message_port_pub(pmt::intern("bursts_out"), new_msg);
-          }
-        }
+      // Nothing to do...
+      if (d_fn_ref == 0xffffffff)
+        return;
+
+      pmt::pmt_t blob = pmt::cdr(msg_in);
+
+      // Extract GSMTAP header from message
+      gsmtap_hdr *header = (gsmtap_hdr *) pmt::blob_data(blob);
+      uint32_t frame_nr = be32toh(header->frame_number);
+      uint32_t ts_num = header->timeslot;
+
+      time_format txtime = fn_time_delta_cpp(d_fn_ref, d_time_ref,
+        frame_nr, d_time_hint, ts_num, d_ts_ref);
+
+      time_spec_t txtime_spec = time_spec_t(txtime.first, txtime.second);
+      txtime_spec -= d_delay_correction;
+      txtime_spec -= d_timing_advance;
+
+      // FIXME: better name?
+      time_spec_t foo = time_spec_t(d_time_hint.first, d_time_hint.second);
+
+      // Drop too late / early bursts
+      if (txtime_spec <= foo) {
+        std::cout << "lB" << std::flush;
+        return;
+      } else if (txtime_spec > foo + 10.0) {
+        std::cout << "eB" << std::flush;
+        return;
+      }
+
+      pmt::pmt_t tags_dict = pmt::dict_add(
+        pmt::make_dict(),
+        pmt::intern("tx_time"),
+        pmt::make_tuple(
+          pmt::from_uint64(txtime_spec.get_full_secs()),
+          pmt::from_double(txtime_spec.get_frac_secs()))
+      );
+
+      tags_dict = pmt::dict_add(tags_dict,
+        pmt::intern("fn"), pmt::from_uint64(frame_nr));
+      tags_dict = pmt::dict_add(tags_dict,
+        pmt::intern("ts"), pmt::from_uint64(ts_num));
+
+      // Send a message to the output
+      pmt::pmt_t msg_out = pmt::cons(tags_dict, pmt::cdr(msg_in));
+      message_port_pub(pmt::mp("bursts_out"), msg_out);
     }
 
-    void txtime_setter_impl::set_fn_time_reference(uint32_t fn, uint32_t ts, uint64_t time_secs, double time_fracs)
+    void txtime_setter_impl::set_fn_time_reference(
+      uint32_t fn, uint32_t ts, uint64_t time_secs,
+      double time_fracs)
     {
       d_fn_ref = fn;
       d_ts_ref = ts;
@@ -130,7 +172,8 @@
       set_time_hint(time_secs, time_fracs);
     }
 
-    void txtime_setter_impl::set_time_hint(uint64_t time_hint_secs, double time_hint_fracs)
+    void txtime_setter_impl::set_time_hint(
+      uint64_t time_hint_secs, double time_hint_fracs)
     {
       d_time_hint = std::make_pair(time_hint_secs, time_hint_fracs);
     }
@@ -147,4 +190,3 @@
 
   } /* namespace gsm */
 } /* namespace gr */
-
diff --git a/lib/transmitter/txtime_setter_impl.h b/lib/transmitter/txtime_setter_impl.h
index e3f195a..62f500a 100644
--- a/lib/transmitter/txtime_setter_impl.h
+++ b/lib/transmitter/txtime_setter_impl.h
@@ -39,15 +39,20 @@
       time_format d_time_hint;
       double d_timing_advance;
       double d_delay_correction;
-      
+
+      void process_fn_time_reference(pmt::pmt_t msg);
+      void process_txtime_of_burst(pmt::pmt_t msg);
+
      public:
-      txtime_setter_impl(uint32_t init_fn, uint64_t init_time_secs, double init_time_fracs, uint64_t time_hint_secs, double time_hint_fracs, double timing_advance, double delay_correction);
+      txtime_setter_impl(uint32_t init_fn, uint64_t init_time_secs,
+        double init_time_fracs, uint64_t time_hint_secs,
+        double time_hint_fracs, double timing_advance,
+        double delay_correction);
       ~txtime_setter_impl();
 
       // Where all the action really happens
-      void process_fn_time_reference(pmt::pmt_t msg);
-      void process_txtime_of_burst(pmt::pmt_t msg);
-      void set_fn_time_reference(uint32_t fn, uint32_t ts, uint64_t time_secs, double time_fracs);
+      void set_fn_time_reference(uint32_t fn, uint32_t ts,
+        uint64_t time_secs, double time_fracs);
       void set_time_hint(uint64_t time_hint_secs, double time_hint_fracs);
       void set_delay_correction(double delay_correction);
       void set_timing_advance(double timing_advance);
@@ -57,4 +62,3 @@
 } // namespace gr
 
 #endif /* INCLUDED_GSM_TXTIME_SETTER_IMPL_H */
-