diff --git a/ba/ba3800.cpp b/ba/ba3800.cpp
index d39747540..ab1324e13 100755
--- a/ba/ba3800.cpp
+++ b/ba/ba3800.cpp
@@ -76,7 +76,7 @@ public:
   BA3800_application(char livello) : _liv(toupper(livello)) {}
 };
 
-const char * num2str(const TString & s)
+static const char * num2str(const TString & s)
 {
 	TString & str = get_tmp_string(20);