Private Sub Command1_Click()
    Dim nFic As Integer
    Dim sFic As String
    Dim sCadena As String

    'sCadena tiene 20 caracteres
    sCadena = "Prueba de una cadena"

    sFic = "hola.exe"
    nFic = FreeFile
    Open sFic For Binary As nFic
    Put nFic, 4647, sCadena ' el 4647 es el offset donde se empieza a escribir
    Close nFic

    'leer los datos guardados
    nFic = FreeFile
    Open sFic For Binary As nFic
    Get nFic, , sCadena
    Print sCadena
    Close nFic
End Sub