Public Function telc(num As String) As String

    Dim tl As Integer
    Dim ltem, rtem, ttem As String
    Dim ti As Integer
    ttem = ""
    tl = Len(num)
    If tl > 14 Then
        num = Mid(num, 1, 14)
        tl = 14
    End If

    If tl = 11 Then
      tl = tl + 2
      num = "86" & num
    End If
    If tl Mod 2 = 1 Then
         tl = tl + 1
         num = num + "F"
    End If
   
    For ti = 1 To tl Step 2
      ttem = ttem & Mid(num, ti + 1, 1) & Mid(num, ti, 1)
    Next ti
    telc = ttem
   
  End Function