Update rigctld.1 man page

doc/man1/rigctld.1

@@ -205,7 +205,7 @@ in which case it is hexadecimal.
 .BR \-S ", " \-\-separator = \fIchar\fP
 Use char as separator instead of line feed
 .IP
-The default is \n
+The default is \n.  Recommend using $ or @ as they work on both Unix and Windows
 .IP
 .
 .TP