diff --git a/lib/tdm_datatype.hpp b/lib/tdm_datatype.hpp
index 5d48f99..01135ad 100644
--- a/lib/tdm_datatype.hpp
+++ b/lib/tdm_datatype.hpp
@@ -40,6 +40,9 @@ public:
   tdmdatatype(eFloat32Usi num): float32_(num), dtidx_(5) {};
   tdmdatatype(eFloat64Usi num): float64_(num), dtidx_(6) {};
 
+  // identify type
+  short int& dtype() { return dtidx_; }
+
   // overall assignment operator
   tdmdatatype& operator=(const tdmdatatype &num)
   {
@@ -90,14 +93,12 @@ public:
   }
   tdmdatatype& operator=(const eFloat32Usi &num)
   {
-    std::cout<<"tdmdatatype operator= for eFloat32Usi\n";
     this->float32_ = num;
     this->dtidx_ = 5;
     return *this;
   }
   tdmdatatype& operator=(const eFloat64Usi &num)
   {
-    std::cout<<"tdmdatatype operator= for eFloat64Usi\n";
     this->float64_ = num;
     this->dtidx_ = 6;
     return *this;
@@ -105,17 +106,17 @@ public:
 
   // define custom stream operator to print the correct type
   friend std::ostream& operator<<(std::ostream& out, const tdmdatatype& num)
-   {
-     std::cout<<"operator<< dtidx_:"<<num.dtidx_<<"\n";
-          if ( num.dtidx_ == 0 ) out<<num.sint16_;
-     else if ( num.dtidx_ == 1 ) out<<num.sint32_;
-     else if ( num.dtidx_ == 2 ) out<<num.uint8_;
-     else if ( num.dtidx_ == 3 ) out<<num.uint16_;
-     else if ( num.dtidx_ == 4 ) out<<num.uint32_;
-     else if ( num.dtidx_ == 5 ) out<<num.float32_;
-     else if ( num.dtidx_ == 6 ) out<<num.float64_;
-     return out;
-   }
+  {
+    if ( num.dtidx_ == 0 ) out<<num.sint16_;
+    else if ( num.dtidx_ == 1 ) out<<num.sint32_;
+    else if ( num.dtidx_ == 2 ) out<<num.uint8_;
+    else if ( num.dtidx_ == 3 ) out<<num.uint16_;
+    else if ( num.dtidx_ == 4 ) out<<num.uint32_;
+    else if ( num.dtidx_ == 5 ) out<<num.float32_;
+    else if ( num.dtidx_ == 6 ) out<<num.float64_;
+    return out;
+  }
+
 };
 
 // // base class for all tdm datatypes
diff --git a/lib/tdm_reaper.cpp b/lib/tdm_reaper.cpp
index 7df25df..c35aa95 100644
--- a/lib/tdm_reaper.cpp
+++ b/lib/tdm_reaper.cpp
@@ -568,8 +568,8 @@ std::string tdm_reaper::get_block_overview(format formatter)
 // -------------------------------------------------------------------------- //
 
 // extract channel by id
-template<typename tdmtype>
-std::vector<tdmtype> tdm_reaper::get_channel(std::string& id)
+// template<typename tdmtype>
+std::vector<tdmdatatype> tdm_reaper::get_channel(std::string& id)
 {
   // check for existence of required channel id (=key)
   if ( tdmchannels_.count(id) == 1 )
@@ -592,7 +592,7 @@ std::vector<tdmtype> tdm_reaper::get_channel(std::string& id)
 
     // use "values" id to map to external block
     block blk = tdx_blocks_.at(loccol.external_id_);
-    
+
     // // distinguish numeric datatypes
     // switch ( blk.value_type_ )
     // {
@@ -634,10 +634,14 @@ std::vector<tdmtype> tdm_reaper::get_channel(std::string& id)
     throw std::invalid_argument(std::string("channel id does not exist: ") + id);
   }
 
-  return std::vector<tdmtype>();
+  std::vector<tdmdatatype> data;
+  eFloat32Usi m(4);
+  data.push_back(m);
+  // std::vector<tdmdatatype>();
+  return data;
 }
 
-template std::vector<tdmdatatype> tdm_reaper::get_channel<tdmdatatype>(std::string& id);
+// template std::vector<tdmdatatype> tdm_reaper::get_channel<tdmdatatype>(std::string& id);
 
 // std::vector<double> tdm_reaper::get_channel(std::string &id)
 // {
diff --git a/lib/tdm_reaper.hpp b/lib/tdm_reaper.hpp
index edc694b..0614774 100644
--- a/lib/tdm_reaper.hpp
+++ b/lib/tdm_reaper.hpp
@@ -180,8 +180,8 @@ public:
   }
 
   // extract channel by id
-  template<typename tdmtype>
-  std::vector<tdmtype> get_channel(std::string& id);
+  // template<typename tdmtype>
+  std::vector<tdmdatatype> get_channel(std::string& id);
 
   // (TODO introduce template T to reference specific datatype instead of double in general)
   // std::vector<double> get_channel(std::string &id);
diff --git a/src/main.cpp b/src/main.cpp
index 8564f11..626e6e2 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -201,15 +201,14 @@ int main(int argc, char* argv[])
     std::cout<<jack.get_localcolumn_overview(formatter)<<"\n";
     std::cout<<jack.get_block_overview(formatter)<<"\n";
 
-    tdmdatatype A;
-    A = (eUInt8Usi)0.354;
-    std::cout<<A<<"\n";
+    std::string chid("usi14");
+    std::vector<tdmdatatype> chdata = jack.get_channel(chid);
 
-    // std::string chid("usi14");
-    // std::vector<tdmdatatype> chdata = jack.get_channel<tdmdatatype>(chid);
-    //
-    // std::cout<<"channel size: "<<chdata.size()<<"\n";
-    // for ( tdmdatatype el: chdata ) std::cout<<el<<"\n";
+    std::cout<<"channel size: "<<chdata.size()<<"\n";
+    for ( tdmdatatype el: chdata )
+    {
+      std::cout<<el<<":"<<el.dtype()<<"\n";
+    }
 
     // std::vector<std::string> chgrids = jack.get_channelgroup_ids();
     // for ( auto el: chgrids ) std::cout<<el<<",";