diff --git a/grc/transmitter/CMakeLists.txt b/grc/transmitter/CMakeLists.txt
index e512d10..0905e19 100644
--- a/grc/transmitter/CMakeLists.txt
+++ b/grc/transmitter/CMakeLists.txt
@@ -20,5 +20,6 @@
 install(FILES
     gsm_gmsk_mod.xml
     gsm_txtime_bursts_tagger.xml 
-    gsm_txtime_setter.xml DESTINATION share/gnuradio/grc/blocks
+    gsm_txtime_setter.xml 
+    preprocess_tx_burst.xml DESTINATION share/gnuradio/grc/blocks
 )
diff --git a/grc/transmitter/preprocess_tx_burst.xml b/grc/transmitter/preprocess_tx_burst.xml
new file mode 100644
index 0000000..70b447e
--- /dev/null
+++ b/grc/transmitter/preprocess_tx_burst.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<block>
+  <name>Preprocess Tx burst</name>
+  <key>gsm_preprocess_tx_burst</key>
+  <import>import grgsm</import>
+  <make>grgsm.preprocess_tx_burst()</make>
+
+  <sink>
+    <name>bursts_in</name>
+    <type>message</type>
+    <optional>1</optional>
+  </sink>
+
+  <source>
+    <name>bursts_out</name>
+    <type>message</type>
+    <optional>1</optional>
+  </source>
+</block>