diff --git a/lisp/dtk-speak.el b/lisp/dtk-speak.el
index 485a49a..0ed96ba 100644
--- a/lisp/dtk-speak.el
+++ b/lisp/dtk-speak.el
@@ -395,7 +395,7 @@ will set \"en_GB\".
   "Remove all octal chars."
   (let ((inhibit-read-only t))
     (goto-char (point-min))
-    (while (re-search-forward "[\177-\377]+"  nil t )
+    (while (re-search-forward "[^\x0-\x7F]+"  nil t )
       (replace-match " "))))
 
 (defsubst  dtk-fix-brackets (mode)