Try the following:
(char)Int16.Parse("003a", NumberStyles.AllowHexSpecifier);
or
System.Convert.ToChar(System.Convert.ToUInt32("003a", 16));
or
string str = ""; for(int i = 0; i<myHex.Length; i += 4) str += (char)Int16.Parse(myHex.Substring(i, 4), NumberStyles.AllowHexSpecifier);
Marco
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