by default use codepage1252 for metadata including non-ascii characters while missing codepage info

lib/imc_channel.hpp

@@ -496,10 +496,18 @@ namespace imc
     // convert any description, units etc. to UTF-8 (by default)
     void convert_encoding()
     {
+      // actual input codepage
+      std::string cpn;
+
       if ( !codepage_.empty() )
       {
         // construct iconv-compatible name for respective codepage
-        std::string cpn = std::string("CP") + codepage_;
+        cpn = std::string("CP") + codepage_;
+      }
+      else {
+	// assume codepage 1252 by default
+	cpn = std::string("CP1252");
+      }
 
       // set up converter
       std::string utf = std::string("UTF-8");
@@ -518,7 +526,6 @@ namespace imc
       conv.convert(group_name_);
       conv.convert(group_comment_);
     }
-    }
 
     // get info string
     std::string get_info(int width = 20)