diff --git a/src/protocols/RTTY.h b/src/protocols/RTTY.h
index 89fe933b..96781246 100644
--- a/src/protocols/RTTY.h
+++ b/src/protocols/RTTY.h
@@ -11,10 +11,10 @@
 // ITA2 character table: - position in array corresponds to 5-bit ITA2 code
 //                       - characters to the left are in letters shift, characters to the right in figures shift
 //                       - characters marked 0x7F do not have ASCII equivalent
-const char ITA2Table[ITA2_LENGTH][2] = {{'\0', '\0'}, {'E', '3'}, {'\n', '\n'}, {'A', '-'}, {' ', ' '}, {'S', '\''}, {'I', '8'}, {'U', '7'}, 
-                                        {'\r', '\r'}, {'D', 0x05}, {'R', '4'}, {'J', '\a'}, {'N', ','}, {'F', '!'}, {'C', ':'}, {'K', '('}, 
-                                        {'T', '5'}, {'Z', '+'}, {'L', ')'}, {'W', '2'}, {'H', 0x7F}, {'Y', '6'}, {'P', '0'}, {'Q', '1'}, 
-                                        {'O', '9'}, {'B', '?'}, {'G', '&'}, {0x7F, 0x7F}, {'M', '.'}, {'X', '/'}, {'V', ';'}, {0x7F, 0x7F}};
+static const char ITA2Table[ITA2_LENGTH][2] = {{'\0', '\0'}, {'E', '3'}, {'\n', '\n'}, {'A', '-'}, {' ', ' '}, {'S', '\''}, {'I', '8'}, {'U', '7'}, 
+                                               {'\r', '\r'}, {'D', 0x05}, {'R', '4'}, {'J', '\a'}, {'N', ','}, {'F', '!'}, {'C', ':'}, {'K', '('}, 
+                                               {'T', '5'}, {'Z', '+'}, {'L', ')'}, {'W', '2'}, {'H', 0x7F}, {'Y', '6'}, {'P', '0'}, {'Q', '1'}, 
+                                               {'O', '9'}, {'B', '?'}, {'G', '&'}, {0x7F, 0x7F}, {'M', '.'}, {'X', '/'}, {'V', ';'}, {0x7F, 0x7F}};
 
 class ITA2String {
   public: