--- a/docs/administration/adding_channels.rst	Tue Mar 25 09:36:33 2014 +0200
+++ b/docs/administration/adding_channels.rst	Wed Apr 30 14:49:05 2014 +0300
@@ -1,10 +1,16 @@
-Adding channels
-===============
+Channels
+========
 
 
 
 .. _signal-types:
 
 Signal types
-~~~~~~~~~~~~
-(explain here all the signal type abreviations).
+------------
+(explain here all the signal type abbreviations).
+
+
+Connection channels to systems
+------------------------------
+
+Each channels should be connected to at least one system.