Copy and Paste down at time interval

Hi

I am a very basic excel user and need help with some VBA please :-)

I would like the value in cell F3 (which changes) to be copied and pasted down to F4 at a 30 sec interval, at the next 30 sec interval the value in F4 would move to F5 and a new "latest value" posted from F3 TO F4 and so on.

Ideally would like a start and end time, so only does the function between these hours and is it not in these houses it pauses.

Thanks in advance for any help.

See attached file, I hope that does what you need.
Code used in the sheet:

Private Sub Worksheet_Change(ByVal Target As Range)
   If Target.Cells.Count = 1 And Target.Address(0, 0) = "F3" Then
      If Not timerOn Then
         Call Module1.StartClock
      End If
   End If
End Sub

Code use in module 'Module1':

Global myTime
Global timerOn As Boolean
Sub StartClock()
   With ThisWorkbook.Sheets("Sheet1")
      'Clear total elapsed time
      If .Range("b4") = "" Then
         .Range("b4") = 30
      ElseIf .Range("b4") = 1 Then
         lrow = .Cells(Rows.Count, "f").End(xlUp).Row
         If lrow > 3 Then
            .Range("f4:f" & lrow).Copy .Range("f5")
         End If
         .Range("f4") = .Range("f3")
         .Range("b4") = 30
         .Range("f3") = ""
         .Range("f3").Select
      Else
         .Range("b4") = .Range("b4") - 1
      End If
   
      If Time >= .Range("b1") And Time <= .Range("b2") Then
         timerOn = True
         nextTick = Now + TimeValue("00:00:01")
         myTime = nextTick
         
         Application.OnTime nextTick, "StartClock"
      Else
         Call StopClock
         .Range("b4").ClearContents
      End If
   End With
End Sub
Sub StopClock()
   'Stop OnTime event.
   'Returns error if already stopped and hense the on error handling.
   On Error Resume Next
   
   timerOn = False
   Application.OnTime _
      EarliestTime:=myTime, _
      Procedure:="StartClock", _
      Schedule:=False
   
   If Err.Number > 0 Then Exit Sub
   
   On Error GoTo 0
   With ThisWorkbook.Sheets("Sheet1")
      .Range("j3").Value = .Range("j1").Value - .Range("j2").Value
   End With
End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
   If Target.Cells.Count = 1 And Target.Address(0, 0) = "F3" Then
      With ThisWorkbook.Sheets("Sheet1")
         If Time >= .Range("b1") And Time <= .Range("b2") Then
            .Range("b4") = 30
            Call StartClock
         End If
      End With
   End If
End Sub

Regards,
Antonio

In attached file I disabled the code that clear contents of Range F3 that you desired.

Regards,
Antonio