Please refer to the attached png
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>
<%@ Register assembly="Telerik.Web.UI" namespace="Telerik.Web.UI" tagprefix="telerik" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script type="text/javascript">
function OnPopupOpening(sender, args) {
var MDate = sender.get_minDate();
sender.set_minDate(2013 + '-' + 3 + '-' + 13 + '-' + 6 + '-' + 00 + '-' + 0 + '-' + 0);
var MDateAfter = sender.get_minDate();
var TWStartTime = sender._timeView.get_startTime();
sender._timeView.set_startTime(6 + '-' + 00 + '-' + 0 + '-0-0');
var TWStartTimeAfter = sender._timeView.get_startTime();
var picker = $find("<%= RadDateTimePicker2.ClientID %>");
var timeview = sender.get_timeView();
var NDate = new Date(2013, 2, 13, 6, 0, 0, 0);
$telerik.toTimeView(timeview).set_startTime(NDate);
var TWStartTimeAfter = sender._timeView.get_startTime();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<telerik:RadScriptManager ID="RadScriptManager1" Runat="server">
</telerik:RadScriptManager>
<telerik:RadDateTimePicker ID="RadDateTimePicker1" Runat="server"
Culture="en-US"
HiddenInputTitleAttibute="Visually hidden input created for functionality purposes."
WrapperTableSummary="Table holding date picker control for selection of dates.">
<TimeView CellSpacing="-1" interval="00:30:00"></TimeView>
<TimePopupButton ImageUrl="" HoverImageUrl=""></TimePopupButton>
<Calendar UseRowHeadersAsSelectors="False" UseColumnHeadersAsSelectors="False" ViewSelectorText="x"></Calendar>
<DateInput DisplayDateFormat="M/d/yyyy" DateFormat="M/d/yyyy" LabelWidth="40%"></DateInput>
<DatePopupButton ImageUrl="" HoverImageUrl=""></DatePopupButton>
</telerik:RadDateTimePicker>
</div>
<div>
<telerik:RadDateTimePicker ID="RadDateTimePicker2" Runat="server"
Culture="en-US"
HiddenInputTitleAttibute="Visually hidden input created for functionality purposes."
WrapperTableSummary="Table holding date picker control for selection of dates.">
<TimeView CellSpacing="-1" interval="00:30:00"></TimeView>
<TimePopupButton ImageUrl="" HoverImageUrl=""></TimePopupButton>
<Calendar UseRowHeadersAsSelectors="False" UseColumnHeadersAsSelectors="False" ViewSelectorText="x"></Calendar>
<DateInput DisplayDateFormat="M/d/yyyy" DateFormat="M/d/yyyy" LabelWidth="40%"></DateInput>
<DatePopupButton ImageUrl="" HoverImageUrl=""></DatePopupButton>
<ClientEvents OnPopupOpening="OnPopupOpening" />
</telerik:RadDateTimePicker>
</div>
<telerik:RadButton ID="RadButton1" runat="server" Text="RadButton">
</telerik:RadButton>
</form>
</body>
</html>