Public Function CheckBIG(strSource As String) As Boolean
Dim idx As Long
Dim ByteTemp() As Byte
CheckBIG = False
For idx = 1 To Len(strSource)
    ByteTemp = StrConv(Mid(strSource, idx, 1), vbFromUnicode)
    If UBound(ByteTemp) > 0 Then
        If (ByteTemp(1) >= 64) And (ByteTemp(1) <= 126) Then
            CheckBIG = True
            Exit For
        End If
    End If
Next idx
End Function