grc/receiver/gsm_sch_detector.xml

<?xml version="1.0"?>
<block>
  <name>SCH Bursts Detector</name>
  <key>gsm_sch_detector</key>
  <import>import grgsm</import>
  <make>grgsm.sch_detector($OSR)</make>
  <callback>set_OSR($OSR)</callback>
  <param>
    <name>OSR</name>
    <key>OSR</key>
    <value>4</value>
    <type>int</type>
  </param>

  <sink>
    <name>in</name>
    <type>complex</type>
  </sink>

  <source>
    <name>out</name>
    <type>complex</type>
  </source>
</block>