C# - Hex-Ascii to string

public static string Hex2String(string hex)
{
   string result = "";
   int count = hex.Length / 2;
   int s;

   for (s = 0; s < count; s++)
   {
      string zeichen = hex.Substring(s * 2, 2);
      result += (char)               Convert.ToUInt16(zeichen, 16);
   }

   return result;
}