Private Sub frm_CAS1000_KeyDown(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown
        ton_rechts = True
        Select Case e.KeyCode
            Case Keys.Up
                Me.lauter()
            Case Keys.Down
                Me.leiser()
            Case Keys.Left
                Me.frew_down()
            Case Keys.Right
                Me.freq_up()
        End Select
    End Sub