Index: trunk/Ohana/src/opihi/dvo/avperiodomatch.c
===================================================================
--- trunk/Ohana/src/opihi/dvo/avperiodomatch.c	(revision 41341)
+++ trunk/Ohana/src/opihi/dvo/avperiodomatch.c	(revision 41379)
@@ -367,4 +367,5 @@
   gprint (GP_ERR, "USAGE: avperiodomatch (output) (RA) (DEC) (RADIUS) -where-measure (expression)\n");
   gprint (GP_ERR, "  NOTE: the optional -where-measure (expression) MUST come after the required arguments\n");
+  gprint (GP_ERR, "   RADIUS is in arcseconds\n");
   return (FALSE);
 }