Updated spectral display to used dBm scale and removed baseline/amplification items.

Updated sample handling code to use -1.0 to 1.0 float values throughout, to support P25 decoder and symbol filter.

src/controller/state/ChannelStateList.java

@@ -53,6 +53,8 @@ import decode.mpt1327.MPT1327ChannelState;
 import decode.mpt1327.MPT1327Panel;
 import decode.nbfm.NBFMChannelState;
 import decode.nbfm.NBFMPanel;
+import decode.p25.P25ChannelState;
+import decode.p25.P25Panel;
 import decode.passport.PassportChannelState;
 import decode.passport.PassportPanel;
 
@@ -229,6 +231,10 @@ public class ChannelStateList extends JPanel implements ChannelEventListener
     				}
     			}
     		}
+    		else if( state instanceof P25ChannelState )
+    		{
+    			panel = new P25Panel( channel );
+    		}
     		
     		if( panel != null )
     		{